Use of pelletized metal-modified materials in induction melting furnaces.

Abstract

Inventive techniques for forming unique compositions are disclosed, as well as various advantageous physical characteristics and associated properties of the resulting materials. In particular, the metal(s) (including various alloys such as Inconel superalloys) are characterized by having carbon located within their metal lattice structure. The carbon resides primarily or entirely in interstitial sites within the metal lattice, and may be present in amounts ranging from about 15% to about 90% by weight. Furthermore, the carbon forms nonpolar covalent bonds with both the metal atoms and other carbon atoms present within the lattice. This promotes a substantially uniform distribution of carbon throughout the resulting material, imparting unique and advantageous properties, such as strength-to-weight ratio, density, mechanical toughness, shear strength, flexural strength, hardness, corrosion resistance, electrical and / or thermal conductivity, as described herein. In some approaches, the compositions can be powdered or pelletized.

Description

[Technical Field]

[0001] Related Applications This patent application is an international application claiming priority to U.S. Patent Application No. 17 / 957,937, entitled "USING PELLETIZED METAL-DECORATED MATERIALS IN AN INDUCTION MELTING FURNACE," filed September 30, 2022 (subsequently published under the same title as U.S. Patent Publication No. 2023-0145800 on May 11, 2023), and to U.S. Patent Application No. 17 / 957,989, entitled "USING PELLETIZED METAL-DECORATED MATERIALS IN AN INDUCTION MELTING FURNACE," filed September 30, 2022 (subsequently published under the same title as U.S. Patent Publication No. 2023-0040722 on February 9, 2023). The disclosures of all prior applications are considered part of, and incorporated by reference into, this patent application.

[0002] The present disclosure relates generally to the preparation and use of carbon-containing alloys in induction melting furnaces. [Background technology]

[0003] Specialty alloys are refined in vacuum induction melting (VIM) furnaces. The crucibles of such VIM furnaces are used to melt and mix various mixed components (e.g., metals and nonmetals). Once the various components of the melt are mixed, the melt is placed (e.g., poured) into a mold and allowed to cool. Some mixtures include components in powder form. Unfortunately, emotive forces from the induction coil of the VIM furnace act on the powder, causing it to be ejected from the VIM furnace. This prevents the powder from mixing with other components. What is needed is an improved method for using powdered components in a vacuum induction melting furnace.

[0004] As used herein, the term "covetic material" refers to metals infused with nanoscale-sized carbon particles. Covetic materials are desirable for a variety of applications because they possess many physical, chemical, and electrical properties that exceed the capabilities of conventional non-carbon-infused materials. Summary of the Invention [Means for solving the problem]

[0005] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to limit the scope of the claimed subject matter. Moreover, the systems, methods, and devices of the present disclosure each have several innovative aspects, no single one of which is solely responsible for the desirable attributes disclosed herein.

[0006] Various implementations of the subject matter disclosed herein generally relate to apparatus, methods, and various compositions of carbon-metal composite materials. The apparatus is shown and discussed as potentially related to the controlled use of a plasma spray torch apparatus to produce various carbon-metal bonded compositions of matter, generally and in this disclosure referred to as "cobetic materials." In some cases, these materials are metal-modified carbon. In other cases, these materials are carbon-modified metal. In other aspects, carbon can be combined with materials other than metals, such as ceramics, plastics, composites, silicon, and the like, as described in detail herein below.

[0007] One configuration of a plasma spray torch is embodied as an apparatus having a reaction chamber configured to receive a hydrocarbon process gas mixed with a plurality of molten metal nanoscale-sized particles, a microwave energy source operably coupled to supply power to the reaction chamber, and a controller for regulating the microwave energy source to create conditions in the reaction chamber such that the hydrocarbon process gas dissociates into its constituent carbon atoms and single-layer graphene (SLG) or few-layer graphene (FLG) grows from the carbon atoms on the molten metal nanoscale-sized particles to form a plurality of carbon-metal nanoscale-sized particles. In some configurations, the conditions in the reaction chamber cause (i) a first temperature at which the carbon atoms dissolve into the molten metal nanoscale-sized particles, and (ii) a second temperature at which at least a portion of the dissolved carbon atoms combine with the molten metal in a crystallographic arrangement. In some configurations of the apparatus, a cooling zone is utilized to cool the plurality of carbon-metal nanoscale-sized particles into a powder form, which may be collected and stored in a storage vessel juxtaposed to and proximate the reaction chamber.

[0008] According to various implementations, the disclosed inventive concepts may be embodied as a composition of matter having any of the following physical and / or structural characteristics and related properties. Furthermore, these features and / or properties may be included in different combinations or orders according to different embodiments, without limitation.

[0009] In one aspect, the composition comprises one or more particles, each particle independently comprising a metal lattice, the metal lattice having one or more coherent planar layers of graphene disposed therein. Preferably, at least some of the carbon atoms of the one or more coherent planar layers of graphene are disposed in interstitial positions within the metal lattice. More preferably, the one or more coherent planar layers of graphene are interstitially interdigitated between the basal planes of the metal lattice. The graphene can exist as a single layer (e.g., "single-layer graphene" or "SLG") or as multiple layers (e.g., 2, 3, 5, 10, or any number up to 15 layers (also referred to herein as "few-layer graphene" or "FLG")). At least some of the carbon atoms of one or more layers of graphene are covalently bonded to metal atoms of the metal lattice, and the covalent bond between the carbon atoms and the metal atoms is or includes a nonpolar covalent bond. In some embodiments, the covalent bond can consist essentially or entirely of a nonpolar covalent bond. Similarly, carbon atoms in one or more layers of graphene can be covalently bonded to other carbon atoms in one or more layers of graphene, and these covalent bonds can comprise, consist essentially of, or consist entirely of non-polar covalent bonds, according to different implementations. Thus, one or more particles can substantially or completely exclude polar covalent bonds. Similarly, the metal lattice of each particle can substantially or completely exclude ionic bonds. Each of the one or more layers of graphene is preferably substantially defect-free, such that the graphene is "pristine." Preferably, each particle is also characterized by a substantial, or more preferably complete, absence of carbon aggregate(s) and / or agglomerate(s) at the grain boundaries and / or surface(s) of the metal lattice. The inventive processing techniques described herein result in particle(s) with total carbon loadings ranging from about 15% to about 90% by weight, with various intermediate loadings also being demonstrated (e.g., in various implementations, about 20%, about 25%, about 33%, about 40%, about 50%, about 60%, about 75%, or up to 90% by weight).The particles may further be characterized by having a diameter ranging from about 20 nm to about 3.5 μm and / or a maximum discernible feature size ranging from about 0.1 nm to about 1 μm. In some implementations, the particles may be compressed into pellets.

[0010] According to another aspect, a composition includes an Inconel alloy having carbon disposed in its metal lattice. Preferably, at least a portion of the carbon is disposed in interstitial sites of the metal lattice, and more preferably, the carbon is substantially uniformly distributed throughout the metal lattice. Furthermore, in some implementations, the grain boundaries of the composition and / or the surfaces of the metal lattice are substantially free of carbon aggregate(s) and / or agglomerate(s). Thus, the maximum distinguishable feature size of the composition may range from about 0.1 nm to about 1 μm. At least some of the carbon atoms are covalently bonded to metal atoms of the metal lattice, and the covalent bonds between the carbon atoms and the metal atoms are or include nonpolar covalent bonds. In some embodiments, the covalent bonds may consist essentially or entirely of nonpolar covalent bonds. Similarly, carbon atoms can be covalently bonded to other carbon atoms, and these covalent bonds may include, consist essentially of, or consist entirely of nonpolar covalent bonds, according to different implementations. Thus, one or more compositions may substantially or completely exclude polar covalent bonds. Similarly, the metal lattice may substantially or completely exclude ionic bonds.

[0011] According to yet another aspect, the composition includes a metal lattice having at least about 15% by weight of carbon disposed therein. Preferably, at least a portion of the carbon is disposed in interstitial sites of the metal lattice, and more preferably, the carbon is substantially uniformly distributed throughout the metal lattice. Furthermore, in some implementations, the grain boundaries of the composition and / or the surfaces of the metal lattice are substantially free of carbon aggregate(s) and / or agglomerate(s). Thus, the maximum distinguishable feature size of the composition may range from about 0.1 nm to about 1 μm. At least some of the carbon atoms are covalently bonded to metal atoms of the metal lattice, and the covalent bonds between the carbon atoms and the metal atoms are or include nonpolar covalent bonds. In some embodiments, the covalent bonds may consist essentially or entirely of nonpolar covalent bonds. Similarly, carbon atoms can be covalently bonded to other carbon atoms, and these covalent bonds may include, consist essentially of, or consist entirely of nonpolar covalent bonds, according to different implementations. Thus, one or more compositions may substantially or completely exclude polar covalent bonds. Similarly, the metal lattice may substantially or completely exclude ionic bonds.

[0012] In various implementations of the aforementioned aspects, the metal lattice can include one or more metals selected from the group consisting of aluminum, copper, iron, nickel, titanium, tantalum, tungsten, chromium, molybdenum, cobalt, manganese, niobium, and combinations thereof. Accordingly, the metal lattice can be characterized by a crystal structure such as face-centered cubic (FCC), body-centered cubic (BCC), or hexagonal close-packed (HCC). Furthermore, the metal lattice can include carbon in the range of about 15% to about 90% by weight (e.g., about 20%, about 25%, about 33%, about 40%, about 50%, about 60%, about 75%, or up to 90% by weight in various implementations). Carbon is preferably present in interstitial sites of the metal lattice. In some approaches, the metal(s) can be present in the form of an alloy(s). For example, in a particularly preferred approach, the metal is present in the form of one or more Inconel alloys, such as Inconel 600, Inconel 617, Inconel 625, Inconel 690, Inconel 718, and / or Inconel X-750. Even more preferably, the Inconel alloy(s) are superalloy(s).

[0013] In some embodiments, the technology described herein relates to a composition comprising one or more particles, wherein the one or more particles independently comprise a metal lattice, the metal lattice having graphene disposed at interstitial sites of the metal lattice.

[0014] In some aspects, the technology described herein relates to compositions characterized in that at least a portion of the graphene has a structure comprising one or more coherent planar layers.

[0015] In some aspects, the technology described herein relates to compositions in which at least a portion of the graphene is interstitially interdigitated between the basal planes of a metal lattice.

[0016] In some aspects, the technology described herein relates to compositions in which the graphene is substantially free of crystallographic defects.

[0017] In some aspects, the technology described herein relates to compositions in which one or more particles are characterized by carbon aggregate(s) and / or a lack of carbon aggregate(s) at their grain boundaries.

[0018] In some embodiments, the technology described herein relates to compositions in which one or more particles independently comprise between about 15% by weight and about 90% by weight of carbon, and the metal lattice comprises between about 15% by weight and about 60% by weight of carbon arranged in its interstitial positions.

[0019] In some aspects, the technology described herein relates to compositions in which at least a portion of the graphene is pure.

[0020] In some aspects, the technology described herein relates to a composition comprising one or more particles, wherein the one or more particles independently comprise a metal lattice having graphene disposed therein, each particle characterized by carbon aggregate(s) and / or a lack of carbon aggregate(s) at its grain boundaries.

[0021] In some aspects, the technology described herein relates to compositions characterized in that at least a portion of the graphene has a structure comprising one or more coherent planar layers.

[0022] In some aspects, the technology described herein relates to compositions in which at least a portion of the graphene is located in interstitial sites of a metal lattice.

[0023] In some aspects, the technology described herein relates to compositions in which at least a portion of the graphene is interstitially interdigitated between the basal planes of a metal lattice.

[0024] In some aspects, the technology described herein relates to compositions in which the graphene is substantially free of crystallographic defects.

[0025] In some embodiments, the technology described herein relates to compositions in which one or more particles independently comprise between about 15% by weight and about 90% by weight of carbon, and the metal lattice comprises between about 15% by weight and about 60% by weight of carbon arranged in its interstitial positions.

[0026] In some aspects, the technology described herein relates to compositions in which at least a portion of the graphene is pure.

[0027] In some embodiments, the technology described herein relates to a composition comprising one or more particles, wherein the one or more particles independently comprise a metal lattice, the metal lattice having graphene disposed therein, the graphene being substantially free of crystallographic defects.

[0028] In some aspects, the technology described herein relates to compositions characterized in that at least a portion of the graphene has a structure comprising one or more coherent planar layers.

[0029] In some aspects, the technology described herein relates to compositions in which at least a portion of the graphene is located in interstitial sites of a metal lattice.

[0030] In some aspects, the technology described herein relates to compositions in which at least a portion of the graphene is interstitially interdigitated between the basal planes of a metal lattice.

[0031] In some aspects, the technology described herein relates to compositions in which each particle is characterized by carbon aggregate(s) and / or a lack of carbon aggregate(s) at its grain boundaries.

[0032] In some embodiments, the technology described herein relates to compositions in which one or more particles independently comprise between about 15% by weight and about 90% by weight of carbon, and the metal lattice comprises between about 15% by weight and about 60% by weight of carbon arranged in its interstitial positions.

[0033] In some aspects, the technology described herein relates to compositions in which at least a portion of the graphene is pure.

[0034] In some aspects, the technology described herein relates to a composition comprising one or more particles, some or all of the particles independently comprising a polymer matrix, the polymer matrix having one or more coherent planar layers of graphene disposed therein.

[0035] In some aspects, the technology described herein relates to compositions in which at least some of the carbon atoms of one or more coherent planar layers of graphene are arranged in interstitial positions within a polymer matrix.

[0036] In some aspects, the technology described herein relates to compositions in which one or more coherent planar layers of graphene are interstitially interdigitated between the basal planes of a polymer matrix.

[0037] In some aspects, the technology described herein relates to compositions in which the polymer matrix comprises one or more polymeric components or one or more polymeric precursors.

[0038] In some aspects, the technology described herein relates to compositions wherein the one or more polymer components are selected from thermoplastic olefin(s), thermoplastic polyolefin(s), olefin-based thermoplastic elastomer-type structure(s), thermoplastic polymer, photopolymer, liquid crystal polymer, crosslinked polymer, acrylic, copolymer, hybrid crosslinked polymer, epoxy, silicone, acrylic polyol, aliphatic polyisocyanate, urethane acrylate, vinyl alcohol, vinyl halide, acrylamide, diazonium salt(s), diaryliodonium salt(s), triarylsulfonium salt(s), alkylsulfonium salt(s), iron arene salt(s), sulfonyloxyketone(s), triarylsiloxysiloxane(s), and combinations thereof, and the one or more polymer precursors are one or more precursors of the polymer component.

[0039] In some aspects, the technology described herein provides a method for preparing a polymeric composition comprising one or more polymeric components, independently selected from the group consisting of polytrimethylene terephthalate, polyethersulfone, high density polyethylene, low density polyethylene, linear low density polyethylene, polypropylene, polyolefin copolymers, polystyrene, polystyrene copolymers, polythene, polyvinyl halides, polyvinyl alcohol, polytetrafluoroethylene (TEFLON®), polyacrylates, polymethacrylates, polyesters, polyvinyl chloride, fluoropolymers, polyamides, polyamide-imides, polyetherimides, polyphenylene sulfide, polysulfones, polyacetals, polycarbonates, polyphenylene oxides, polyurethanes, thermoplastic elastomers, epoxies, alkyds, melamines, phenolics, ureas, vinyl esters, and the like; epoxies, ciabatta ... and a combination thereof.

[0040] In some aspects, the technology described herein provides a method for preparing a polymeric composite, wherein the one or more polymer precursors are independently selected from the group consisting of polytrimethylene terephthalate, polyethersulfone, high density polyethylene, low density polyethylene, linear low density polyethylene, polypropylene, polyolefin copolymer, polystyrene, polystyrene copolymer, polythene, polyvinyl halide, polyvinyl alcohol, polytetrafluoroethylene (PTFE), polyacrylate, polymethacrylate, polyester, polyvinyl chloride, fluoropolymer, polyamide, polyamide-imide, polyetherimide, polyphenylene sulfide, polysulfone, polyacetal, polycarbonate, polyphenylene oxide, polyurethane, thermoplastic elastomer, epoxy, alkyd, melamine, phenolic, urea, vinyl ester, epoxy, cyanate ester, polyurethane, The composition is selected from precursors of acrylonitrile butadiene styrene (ABS), polyacrylonitrile (PAN), ethylene vinyl alcohol, poly(methyl methacrylate) (PMMA), polyvinyl cinnamate, polyisoprene, polyimide, styrenic block copolymers, bitumen, nitrile rubber, polycarbonate, polyetherimide (PEI), poly(phenylene sulfide) (PPS), polyetheretherketone (PEEK), polyetherketone (PEK), polyetherketoneketone (PEKK), polyaryletherketone (PAEK), polylactic acid (PLA), polybenzimidazole (PBI), polyetherimide (PEI), polyethersulfone (PES), polyphenylene sulfide (PPS), polyphthalamide (PPA), polyamide (6, 11, 6.6, 12, etc.) (PAS), and combinations thereof.

[0041] In some aspects, the technology described herein relates to compositions wherein the polymer matrix further comprises one or more additional components selected from a crosslinker, a binder, an initiator, a terminator, a phase change material, a solvent system, a carbonaceous material, a thermosetting system, and combinations thereof.

[0042] In some aspects, the technology described herein relates to compositions wherein one or more coherent planar layers of graphene consist of a monolayer of graphene.

[0043] In some aspects, the technology described herein relates to compositions wherein the one or more coherent planar layers of graphene comprise at least 5 layers of graphene and no more than 15 layers of graphene.

[0044] In some aspects, the technology described herein relates to compositions in which at least some of the carbon atoms of one or more layers of graphene are covalently bonded to atoms of a polymer matrix.

[0045] In some aspects, the technology described herein relates to compositions wherein the covalent bonds between the carbon atoms of the graphene and the atoms of the polymer matrix comprise non-polar covalent bonds.

[0046] In some aspects, the technology described herein relates to compositions in which at least some of the carbon atoms in one or more layers of graphene are covalently bonded to other carbon atoms in one or more layers of graphene.

[0047] In some aspects, the technology described herein relates to compositions in which the covalent bonds between the carbon atoms of the graphene comprise non-polar covalent bonds.

[0048] In some aspects, the technology described herein relates to compositions in which one or more particles substantially exclude polar covalent bonds.

[0049] In some aspects, the technology described herein relates to compositions in which the polymer matrix of one or more particles substantially eliminates ionic bonding.

[0050] In some aspects, the technology described herein relates to compositions in which one or more coherent planar layers of graphene are substantially free of defects.

[0051] In some embodiments, the technology described herein relates to compositions in which one or more particles independently comprise between about 15% carbon by weight and about 90% carbon by weight.

[0052] In some aspects, the technology described herein relates to compositions in which the polymer matrix contains from about 15% to about 60% by weight of carbon in interstitial positions.

[0053] In some aspects, the technology described herein relates to a composition, wherein at least a portion of the polymer matrix is ​​characterized by a crystallinity ranging from greater than 0% to about 50%, and at least a portion of the graphene crosslinks the crystalline structure of at least a portion of the composition via epitaxy.

[0054] In some aspects, the technology described herein relates to compositions in which each particle is characterized by a lack of carbon aggregate(s) and / or agglomerate(s) at its grain boundaries.

[0055] In some aspects, the technology described herein relates to compositions in which the one or more particles are each characterized by a diameter ranging from about 20 nm to about 3.5 μm.

[0056] In some aspects, the technology described herein relates to a composition, wherein the maximum distinguishable feature size of the composition ranges from about 0.1 nm to about 1 μm.

[0057] In some aspects, the technology described herein relates to compositions in which one or more particles are compressed into a pellet.

[0058] In some aspects, the technology described herein relates to electrochemical cells that include the compositions. In some aspects, the technology described herein relates to electrochemical cells, where the electrochemical cells are characterized by a coin configuration.

[0059] In some aspects, the technology described herein relates to electrochemical cells, where the electrochemical cells are characterized by a cylindrical configuration.

[0060] In some aspects, the technology described herein relates to electrochemical cells, the electrochemical cells being characterized by a prismatic configuration.

[0061] In some aspects, the technology described herein relates to electrochemical cells, the electrochemical cells being characterized by a pouch configuration.

[0062] In some aspects, the technology described herein relates to electrochemical cells that do not include or are not coupled to any separate structures that function as current collectors other than the electrodes.

[0063] In some aspects, the technology described herein relates to a method that includes receiving a charge comprising metal particles and carbon particles in a plasma spray torch, using the plasma spray torch to cause in situ nucleation of the charge to synthesize a carbon-containing composite material, and flowing the synthesized carbon-containing composite material onto a substrate, wherein the synthesized carbon-containing composite material forms a surface layer and is tuned based on the tuning feature to enable electron emission cooling through the surface layer.

[0064] In some aspects, the technology described herein relates to methods further comprising conditioning the input based on conditioning characteristics, where the conditioning characteristics include porosity, heat transfer, and / or corrosion resistance.

[0065] In some aspects, the technology described herein relates to methods by which synthesized carbon-containing composite materials are tailored to tolerate repeated thermal stresses.

[0066] In some aspects, the technology described herein relates to methods by which synthesized carbon-containing composite materials are tailored to be electrically conductive.

[0067] In some aspects, the technology described herein relates to methods by which synthesized carbon-containing composite materials are tailored to allow for passive thermal control and active thermal control, where passive thermal control is based, at least in part, on the porosity of the synthesized carbon-containing composite material and active thermal control is based, at least in part, on electron emission cooling.

[0068] In some embodiments, the technology described herein relates to methods whereby the synthesized carbon-containing composite material has an RMS roughness in the range of 2.1 mm to 4.7 mm.

[0069] In some aspects, the technology described herein relates to methods whereby the synthesized carbon-containing composite material has a melting point above 1500°C.

[0070] In some aspects, the technology described herein relates to methods whereby the synthesized carbon-containing composite material is resistant to oxidation at temperatures above 1500°C.

[0071] In some aspects, the technology described herein relates to methods by which synthesized carbon-containing composite materials are tailored to have low thermal conductivity.

[0072] In some embodiments, the technology described herein relates to methods wherein the synthesized carbon-containing composite has a thickness of less than 4 mm.

[0073] In some aspects, the technology described herein relates to methods in which some or all of the synthesized carbon-containing composite material includes a bonding layer.

[0074] In some aspects, the technology described herein relates to methods in which the bonding layer is bonded to the substrate by a metal-carbon bond.

[0075] In some aspects, the technology described herein relates to methods in which the bonding layer is a heterogeneous deposit of a synthesized carbon-containing composite material.

[0076] In some aspects, the technology described herein relates to methods in which the bonding layer of the synthesized carbon-containing composite material comprises a metal grid.

[0077] In some aspects, the technology described herein relates to methods wherein the surface layer is hydraulically smooth.

[0078] In some aspects, the technology described herein relates to methods whereby the hydrodynamic smoothness of a surface layer reduces turbulence in the flow of fluid over the surface layer.

[0079] In some aspects, the technology described herein relates to methods where the hydrodynamic smoothness of a surface layer induces laminar fluid flow over the surface layer.

[0080] In some aspects, the technology described herein relates to methods that further include adjusting inputs to optimize temperature redistribution across some or all surface layers of the synthesized carbon-containing composite material.

[0081] In some aspects, the technology described herein relates to a method that includes receiving an input comprising metal particles and carbon particles in a plasma spray torch, using the plasma spray torch to cause in situ nucleation of the input to synthesize a carbon-containing composite material, flowing the synthesized carbon-containing composite material onto a substrate, and forming a hydraulically smooth surface layer based on the synthesized carbon-containing composite material, wherein the hydraulically smooth surface layer is configured to reduce turbulence over the surface layer or to induce laminar flow over the surface layer.

[0082] In some aspects, the technology described herein relates to a method that includes receiving a charge comprising metal particles and carbon particles in a plasma spray torch, using the plasma spray torch to cause in situ nucleation of the charge to synthesize a carbon-containing composite material, the synthesized carbon-containing composite material having an RMS roughness in the range of 2.1 mm to 4.7 mm, and flowing the synthesized carbon-containing composite material onto a substrate.

[0083] In some aspects, the technology described herein relates to a method that includes receiving a charge comprising metal particles and carbon particles in a plasma spray torch, using the plasma spray torch to cause in situ nucleation of the charge to synthesize a carbon-containing composite material, the synthesized carbon-containing composite material being tailored to have low thermal conductivity, and flowing the synthesized carbon-containing composite material onto a substrate.

[0084] In some aspects, the technology described herein relates to a method that includes receiving a charge comprising metal particles and carbon particles in a plasma spray torch, using the plasma spray torch to cause in situ nucleation of the charge to synthesize a carbon-containing composite material, flowing the synthesized carbon-containing composite material onto a substrate, and adjusting the charge to optimize temperature redistribution across some or all of a surface layer of the synthesized carbon-containing composite material.

[0085] In some aspects, the technology described herein relates to a method that includes receiving an input comprising metal particles and carbon particles in a plasma spray torch, causing in situ nucleation of the input using the plasma spray torch to synthesize a carbon-containing composite material, flowing the synthesized carbon-containing composite material onto a substrate, and forming a hydrodynamically smooth surface layer of the substrate based on the synthesized carbon-containing composite material, wherein the hydrodynamically smooth surface layer is configured to reduce turbulence over the substrate or to induce laminar flow over the substrate.

[0086] In some aspects, the technology described herein relates to methods, wherein the substrate is at least one of an aircraft wing, an aircraft surface, a control surface, a vehicle surface, a drone wing, or a drone surface.

[0087] In some aspects, the technology described herein relates to compositions comprising an alloy comprising at least about 40% by weight nickel, at least about 14% by weight chromium, and at least about 3% by weight iron, wherein the alloy is physically characterized by having carbon disposed in a metal lattice of the alloy, at least a portion of the carbon being graphene.

[0088] In some aspects, the technology described herein relates to compositions in which carbon is located in interstitial sites of a metal lattice.

[0089] In some aspects, the technology described herein relates to compositions in which at least some of the carbon atoms are covalently bonded to metal atoms of a metal lattice.

[0090] In some aspects, the technology described herein relates to compositions wherein the covalent bond between the carbon atom and the metal atom comprises a non-polar covalent bond.

[0091] In some aspects, the technology described herein relates to compositions in which at least some of the carbon atoms are covalently bonded to other carbon atoms disposed in a metal lattice.

[0092] In some aspects, the technology described herein relates to compositions wherein the covalent bond between the carbon atoms comprises a non-polar covalent bond.

[0093] In some aspects, the technology described herein relates to compositions, wherein the compositions substantially exclude polar covalent bonds.

[0094] In some aspects, the technology described herein relates to compositions in which the metal lattice substantially eliminates ionic bonding.

[0095] In some embodiments, the technology described herein relates to compositions wherein the metal lattice is characterized by a carbon loading ranging from about 15% to about 90% by weight.

[0096] In some aspects, the technology described herein relates to compositions in which the grain boundaries of the alloy are substantially free of carbon aggregates and / or agglomerates.

[0097] In some aspects, the technology described herein relates to compositions in which the carbon is substantially uniformly distributed throughout the metal lattice.

[0098] In some aspects, the technology described herein relates to a composition, wherein the maximum distinguishable feature size of the composition ranges from about 0.1 nm to about 1 μm.

[0099] In some embodiments, the technology described herein relates to compositions wherein carbon is present in an amount of at least about 1.5% by weight.

[0100] In some aspects, the technology described herein relates to compositions comprising a metal lattice having at least about 15% by weight of carbon arranged in the metal lattice, wherein the metal lattice is characterized by a crystal structure selected from face-centered cubic (FCC), body-centered cubic (BCC), and hexagonal close-packed (HCP).

[0101] In some aspects, the technology described herein relates to compositions in which at least a portion of the carbon is located in interstitial sites of the metal lattice.

[0102] In some aspects, the technology described herein relates to a composition, wherein the grain boundaries of the composition are substantially free of carbon aggregate(s) and / or agglomerate(s).

[0103] In some aspects, the technology described herein relates to compositions wherein the metal grid comprises one or more metals selected from the group consisting of nickel, chromium, aluminum, copper, iron, titanium, tantalum, tungsten, molybdenum, cobalt, manganese, niobium, and alloys thereof.

[0104] In some aspects, the technology described herein relates to compositions in which one or more metals are present in the form of a superalloy.

[0105] In some aspects, the technology described herein relates to compositions in which at least some of the carbon atoms are covalently bonded to metal atoms of a metal lattice.

[0106] In some aspects, the technology described herein relates to compositions wherein the covalent bond between the carbon atom and the metal atom comprises a non-polar covalent bond.

[0107] In some aspects, the technology described herein relates to compositions in which at least some of the carbon atoms are covalently bonded to other carbon atoms disposed in a metal lattice.

[0108] In some aspects, the technology described herein relates to compositions wherein the covalent bond between the carbon atoms comprises a non-polar covalent bond.

[0109] In some aspects, the technology described herein relates to compositions, wherein the compositions substantially exclude polar covalent bonds.

[0110] In some aspects, the technology described herein relates to compositions in which the metal lattice substantially eliminates ionic bonding.

[0111] In some aspects, the technology described herein relates to compositions in which the carbon is substantially uniformly distributed throughout the metal lattice.

[0112] In some aspects, the technology described herein relates to a composition, wherein the maximum distinguishable feature size of the composition ranges from about 0.1 nm to about 1 μm.

[0113] In some aspects, the technology described herein relates to compositions comprising an alloy comprising at least about 40% by weight nickel, at least about 14% by weight chromium, and at least about 3% by weight iron, wherein the alloy is physically characterized by having carbon disposed in a metal lattice of the alloy, at least a portion of the carbon being covalently bonded to metal atoms of the metal lattice.

[0114] In some embodiments, the technology described herein relates to a composition comprising one or more particles, wherein at least a portion of the one or more particles independently comprise a metal lattice, the metal lattice having one or more coherent planar layers of graphene disposed on the metal lattice.

[0115] In some aspects, the technology described herein relates to compositions in which at least some of the carbon atoms of one or more coherent planar layers of graphene are located in interstitial positions within a metal lattice.

[0116] In some embodiments, the technology described herein relates to compositions in which one or more coherent planar layers of graphene are interstitially interdigitated between the basal planes of a metal lattice.

[0117] In some aspects, the technology described herein relates to compositions wherein the metal lattice comprises one or more metals selected from the group consisting of aluminum, copper, iron, nickel, titanium, tantalum, tungsten, chromium, molybdenum, cobalt, manganese, niobium, and combinations thereof.

[0118] In some aspects, the technology described herein relates to compositions wherein one or more coherent planar layers of graphene consist of a monolayer of graphene.

[0119] In some aspects, the technology described herein relates to compositions wherein the one or more coherent planar layers of graphene comprise at least 5 layers of graphene and no more than 15 layers of graphene.

[0120] In some aspects, the technology described herein relates to compositions in which at least some of the carbon atoms in one or more layers of graphene are covalently bonded to metal atoms in a metal lattice.

[0121] In some aspects, the technology described herein relates to compositions wherein the covalent bond between the carbon atom of the graphene and the metal atom comprises a non-polar covalent bond.

[0122] In some aspects, the technology described herein relates to compositions in which at least some of the carbon atoms in one or more layers of graphene are covalently bonded to other carbon atoms in one or more layers of graphene.

[0123] In some aspects, the technology described herein relates to compositions in which the covalent bonds between the carbon atoms of the graphene comprise non-polar covalent bonds.

[0124] In some aspects, the technology described herein relates to compositions in which one or more particles substantially exclude polar covalent bonds.

[0125] In some aspects, the technology described herein relates to compositions in which the metal lattice of each of the one or more particles substantially eliminates ionic bonding.

[0126] In some aspects, the technology described herein relates to compositions in which one or more coherent planar layers of graphene are each independently substantially free of defects.

[0127] In some embodiments, the technology described herein relates to compositions in which one or more particles each independently comprise between about 15% carbon by weight and about 90% carbon by weight.

[0128] In some embodiments, the technology described herein relates to compositions in which the metal lattice contains from about 15% to about 60% by weight of carbon in its interstitial sites.

[0129] In some aspects, the technology described herein relates to compositions in which the metal lattice is characterized by a crystal structure selected from face-centered cubic (FCC), body-centered cubic (BCC), and hexagonal close-packed (HCC).

[0130] In some aspects, the technology described herein relates to compositions in which each particle is characterized by a lack of carbon aggregate(s) and / or agglomerate(s) at its grain boundaries.

[0131] In some aspects, the technology described herein relates to compositions in which the one or more particles are each characterized by a diameter ranging from about 20 nm to about 3.5 μm.

[0132] In some aspects, the technology described herein relates to a composition, wherein the maximum distinguishable feature size of the composition ranges from about 0.1 nm to about 1 μm.

[0133] In some aspects, the technology described herein relates to compositions in which one or more particles are compressed into a pellet.

[0134] The details of one or more implementations of the inventive subject matter described in this disclosure are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages will become apparent from the description, drawings, and claims. It should be noted that the relative dimensions of the following drawings may not be drawn to scale.

[0135] Implementations of the subject matter disclosed herein are illustrated by way of example and not intended to be limited by the figures of the accompanying drawings. Like numbers refer to like elements throughout the drawings and specification. It should be noted that the relative dimensions of the following drawings may not be drawn to scale. [Brief explanation of the drawings]

[0136] [Figure 1A] 1 is a comparative chart illustrating two different Cobetic material forming techniques and examples of materials resulting from each application, according to several implementations. [Figure 1B] 1A-1C show high-resolution transmission electron microscope images and high-resolution energy dispersive spectroscopy X-ray images of materials (e.g., Cobetic materials) produced according to the inventive techniques described herein, according to some implementations. [Figure 2] 1 illustrates a manufacturing process for growing graphene on small molten particles according to one or more of the disclosed implementations. [Figure 3] 1 shows a plasma energy state chart illustrating how a pulsed microwave energy source is used to grow graphene on small molten particles, according to one or more of the disclosed implementations. [Figure 4] 1 illustrates an electronic temperature control technique used to grow graphene on small molten particles according to one or more of the disclosed implementations. [Figure 5] 1 illustrates a dual plasma torch apparatus used to grow graphene on small molten particles according to one or more of the disclosed implementations. [Figure 6] 1 illustrates a pulsed microwave plasma spray torch apparatus adapted for growing graphene on small molten particles according to one or more of the disclosed implementations. [Figure 7] A diagram illustrating the intersection of common subject areas related to Covetic (or related materials), plasma torch spraying, and / or robust synthetic composite carbon coatings, according to one or more of the disclosed implementations. [Figure 8A] FIG. 1 is a schematic diagram illustrating a plasma spray process used to spray carbon particles onto small molten particles according to one or more of the disclosed implementations. [Figure 8B] FIG. 1 is a schematic diagram illustrating a plasma spray process used to spray carbon particles onto small molten particles according to one or more of the disclosed implementations. [Figure 9] 10 is a scanning electron microscope image showing the effect of thermally spraying carbon particles onto small molten particles according to one or more of the disclosed implementations. [Figure 10] 1 shows a chart illustrating a graphene growth temperature profile and a binary phase diagram according to one or more of the disclosed implementations. [Figure 11] FIG. 1 is a cross-sectional view of a conventional plasma flame device. [Figure 12] 1 illustrates a pulsed microwave process flow used in growing graphene on small molten particles according to one or more of the disclosed implementations. [Figure 13] FIG. 1 is a perspective view of a conventional pulsed microwave plasma spray waveguide apparatus used to grow graphene on small molten particles. [Figure 14] FIG. 1 is a schematic diagram of a microwelding technique used to grow graphene on small molten particles, according to one or more of the disclosed implementations. [Figure 15] FIG. 1 is a schematic diagram of a plasma spray apparatus in a coaxial configuration according to one or more of the disclosed implementations. [Figure 16] FIG. 1 is a schematic diagram of a plasma spray apparatus illustrating the evolution of a material as it processes through a series of non-equilibrium energy conditions in accordance with one or more of the disclosed implementations. [Figure 17] 1 illustrates a surface wave plasma system for growing graphene on molten particles according to one or more of the disclosed implementations. [Figure 18A1] 1A-1D illustrate various configurations of a plasma spray reactor according to one or more of the disclosed implementations. [Figure 18A2] 1A-1D illustrate various configurations of a plasma spray reactor according to one or more of the disclosed implementations. [Figure 18B] 1A-1D illustrate various configurations of a plasma spray reactor according to one or more of the disclosed implementations. [Figure 18C] 1A-1D illustrate various configurations of a plasma spray reactor according to one or more of the disclosed implementations. [Figure 18D] 1A-1D illustrate various configurations of a plasma spray reactor according to one or more of the disclosed implementations. [Figure 19] 1 is a chart showing energy versus time during pulse-on and pulse-off in accordance with one or more of the disclosed implementations. [Figure 20A1] 1 is an image showing the organometallic bonding that occurs when combining carbon and copper using a plasma spray torch, according to some of the disclosed implementations. [Figure 20A2] 1 is an image showing a graded composition applied to a substrate material, according to some of the disclosed implementations, showing multiple (e.g., three) material property zones. [Figure 20B] 1 is a material evolution chart illustrating multiple layering configurations that occur upon adding carbon to bulk aluminum in accordance with one or more of the disclosed implementations. [Figure 21A] 1 illustrates an apparatus for thermally spraying a molten mixture of materials onto a substrate, according to an implementation. [Figure 21B-1] 1 illustrates a method for thermally spraying a material (e.g., a covertic material) onto a substrate according to one or more of the disclosed implementations. [Figure 21B-2] 1 illustrates a method for thermally spraying a material (e.g., a covertic material) onto a substrate according to one or more of the disclosed implementations. [Figure 21C] FIG. 1 is a schematic diagram illustrating a plasma spray process used to spray a film according to one or more of the disclosed implementations. [Figure 22A] 1 illustrates an apparatus for coating carbon particles with a molten material, such as a metal, according to one or more of the disclosed implementations. [Figure 22B-1] 1 illustrates a method for coating carbon particles with a molten material, such as a metal, according to one or more of the disclosed implementations. [Figure 22B-2] 1 illustrates a method for coating carbon particles with a molten material, such as a metal, according to one or more of the disclosed implementations. [Figure 23A] 1 illustrates an exemplary deposition technique according to one or more of the disclosed implementations. [Figure 23B] 1 illustrates an exemplary deposition technique according to one or more of the disclosed implementations. [Figure 23C] 1 illustrates an exemplary deposition technique according to one or more of the disclosed implementations. [Figure 23D] 1 illustrates an exemplary deposition technique according to one or more of the disclosed implementations. [Figure 24A] 1 shows a simplified schematic diagram of a material formed via conventional deposition techniques for disposing the material on a substrate in accordance with one or more of the disclosed implementations. [Figure 24B] 1 shows a simplified schematic diagram of a material formed via conventional deposition techniques for disposing the material on a substrate in accordance with one or more of the disclosed implementations. [Figure 25A] 1 shows a simplified schematic diagram of a material formed using an inventive deposition technique that results in non-polar covalent bonds at the surface of a substrate, according to one or more of the disclosed implementations. [Figure 26B] 1 shows a simplified schematic diagram of a material formed using an inventive deposition technique that results in non-polar covalent bonds at the surface of a substrate, according to one or more of the disclosed implementations. [Figure 26A] FIG. 1 shows a schematic diagram illustrating how nonpolar covalent bonds form between square-shaped positions in the face-centered cubic (FCC) structure of aluminum and hexagonal-shaped positions that occur in certain crystallographic structures of carbon. [Figure 26B] FIG. 1 shows a schematic diagram illustrating how nonpolar covalent bonds form between square-shaped positions in the face-centered cubic (FCC) structure of aluminum and hexagonal-shaped positions that occur in certain crystallographic structures of carbon. [Figure 26C]FIG. 1 shows a schematic diagram illustrating how nonpolar covalent bonds form between square-shaped positions in the face-centered cubic (FCC) structure of aluminum and hexagonal-shaped positions that occur in certain crystallographic structures of carbon. [Figure 26D] FIG. 1 shows a schematic diagram illustrating how nonpolar covalent bonds form between square-shaped positions in the face-centered cubic (FCC) structure of aluminum and hexagonal-shaped positions that occur in certain crystallographic structures of carbon. [Figure 26E] FIG. 1 shows a schematic diagram illustrating how nonpolar covalent bonds form between square-shaped positions in the face-centered cubic (FCC) structure of aluminum and hexagonal-shaped positions that occur in certain crystallographic structures of carbon. [Figure 27A] 1 illustrates an exemplary apparatus for producing a material, such as a Covettic material, in powder form, according to one or more of the disclosed implementations. [Figure 27B1] 1 illustrates an exemplary fluidized bed apparatus for cooling and processing powder material, such as powdered covettic, in a fluid, according to one or more of the disclosed implementations. [Figure 27B2] 1 illustrates an exemplary fluidized bed apparatus for cooling and processing powder material, such as powdered covettic, in a fluid, according to one or more of the disclosed implementations. [Figure 27C] FIG. 1 is a schematic diagram illustrating a plasma spray process used to produce a powder material, such as a powdered Cobetic material, according to one or more of the disclosed implementations. [Figure 28-1] 1 illustrates a method for manufacturing components from powdered materials, such as powdered covetic materials, using injection molding techniques, according to some implementations. [Figure 28-2] 1 illustrates a method for manufacturing components from powdered materials, such as powdered covetic materials, using injection molding techniques, according to some implementations. [Figure 29] 1 illustrates various properties of materials described herein (including Covetique materials) according to various embodiments. [Figure 30A1]Problems and solutions associated with melting powders (e.g., metal-modified carbon) are illustrated in comparison to melting the same or similar material in pellet form, according to some embodiments. [Figure 30A2] Problems and solutions associated with melting powders (e.g., metal-modified carbon) are illustrated in comparison to melting the same or similar material in pellet form, according to some embodiments. [Figure 31] 1 illustrates a method for using pellets to minimize or eliminate material emissions during introduction of the pellets into a VIM furnace, according to some embodiments. [Figure 32] 1 illustrates a melt being placed in a mold according to some embodiments. [Figure 33] 1 shows a simplified schematic diagram of a pack processing technique and apparatus according to one embodiment. [Figure 34] 1 shows a simplified schematic of a pack dispersion testing process according to one approach. DETAILED DESCRIPTION OF THE INVENTION

[0137] Aspects of the present disclosure are directed to approaches for producing covetic materials using thermal spray techniques rather than by mixing carbon-based materials into the bulk of a molten metal slurry. Some implementations relate to techniques for reducing the size of interstitial carbon structures to the nanometer (nm) scale. The accompanying drawings and descriptions herein present exemplary environments, systems, and methods for producing "covetic" materials, which are generally understood and defined herein to mean composed of a high concentration (>6% by weight and up to 90% by weight) of carbon, integrated into other materials (such as metals, metal-containing materials, plastics, composites, ceramics, etc., as described herein according to various embodiments) in a manner such that the carbon does not segregate during melting or magnetron sputtering. The resulting materials possess many unique and improved properties over the parent materials from which they are produced. Carbon is dispersed in the (e.g., metal) matrix in several ways that contribute to the enhanced material properties. For example, carbon is very strongly bound to the resulting materials (e.g., covetic materials) and resists many standard methods of detecting and characterizing their morphology. The inclusion of nanoscale carbon increases the melting point and surface tension of the resulting material. Materials produced according to the techniques described herein have higher warm-worked and cold-worked strength.

[0138] Identification and significance of problems and opportunities Metal matrix composites may consist of (at least) a metal or metal alloy (especially a metal made by combining two or more metallic elements to provide higher strength or corrosion resistance) matrix in combination with a higher strength / modulus ceramic, carbon-based reinforcement, or fine fillers in the form of continuous or discontinuous fibers, whiskers, or particles. The size of the reinforcement is important because micrometer-sized reinforced metals can exhibit acceptable levels of improved strength and stiffness over the base alloy. Nevertheless, such improvements can also be accompanied by undesirable reductions in ductility at threshold loads, undesirable yield strength, machinability, and fracture toughness due to undesirable non-uniform distribution of carbon between particles (e.g., at grain boundaries) during processing. To avoid premature cracking and other drawbacks of metal matrix composites containing incompatible micrometer-sized reinforcements, it is essential to reduce the size of the reinforcement phase to the nanometer scale. Furthermore, methods are needed to incorporate the reinforcement phase into the (e.g., metal alloy) matrix, most preferably uniformly.

[0139] Significant increases in mechanical, thermal, electrical, and tribological (referring to the science and engineering of interacting surfaces in relative motion) properties have been observed in response to the addition of the aforementioned carbon-based reinforcements. Notably, these properties can change and / or improve when the size of the reinforcement is reduced from the microscale (e.g., 1–1000 μm) to the nanoscale (e.g., <100 nm) due to increased cohesive forces between the matrix and the particles. The improved properties can be attributed to the formation of strong interfaces that promote efficient strengthening mechanisms. Enhanced tensile and yield strengths have been reported for nanosized particles (approximately 20 nm) compared to microsized particles (approximately 3.5 μm), although nanosized particles have a volume loading that is an order of magnitude lower than that of microsized particles. Therefore, conventional techniques known in the art, such as induction melting and plasma discharge sintering, often fail to provide strengthening at the nanometer scale. Therefore, there is currently a need to reduce the carbon structure containing interstitial vacancies to the nanometer scale.

[0140] Microwave (MW) Plasma Torch Reactor Using a microwave (MW) plasma torch reactor, for example, pure 3D few-layer graphene (FLG) particles can be continuously nucleated in flight in an atmospheric-pressure vapor stream of carbon-containing species, such as methane gas. Such nucleation occurs from initially synthesized carbon-based or carbon-containing "seed" particles. Brilliant, highly structured, and tunable 3D mesoporous carbon-based particles, composed of multiple FLG layers (e.g., 5-15 layers), grow from the carbon-containing seeds, and simultaneously incorporate metal elements or metal-based alloys to form at least partially covalently bonded (and at least partially metallically or ionically bonded) carbon-metal composite (also referred to herein as "cobetic") particle structures. In some implementations, "pure" graphene (referring to graphene that is free of defects or has few defects) is provided or produced with the described MW torch reactor and is unoxidized or has a very low oxygen content (e.g., <1%). In some implementations, the metal (in the resulting cobetic material) is held together by metallic bonds, and the carbon (abundant in graphene or some other organized carbon-based 2D or 3D structure, such as a matrix or lattice) is held together (predominantly) by non-polar covalent bonds. Composite carbon-metal structures may include non-polar covalent bonds between carbon atoms and metal atoms that occur at metal-carbon interfaces. In preferred implementations, the covalent bonds between carbon atoms and / or between carbon atoms and metal atoms present in the composition consist essentially or entirely of non-polar covalent bonds.

[0141] Furthermore, carbon may be present in amounts unattainable using conventional techniques; for example, the resulting material may contain greater than about 6% carbon by weight, greater than about 15% carbon, greater than about 40% carbon, greater than about 60% carbon, or up to about 90% carbon by weight, according to various embodiments. In various embodiments, carbon may be included in the metal lattice in the aforementioned amounts, such that all or substantially all of the carbon is incorporated into the metal (or other material) lattice, and the grain boundaries / lattice surfaces are substantially or completely free of carbon aggregates and / or agglomerates. Furthermore, carbon is preferably located in interstitial sites in the lattice.

[0142] In a particularly preferred embodiment, the material may be provided in the form of a powder having the physical characteristics of a "cobetic" material as described herein. The powder may include a plurality of particles, e.g., particles having diameters of about 20 nm to about 3.5 μm, each particle comprising metal-modified carbon (either in the form of carbon-on-metal or metal-on-carbon) with carbon disposed in a metal lattice as described herein. Most preferably, the particles each independently comprise a metal lattice having one or more (e.g., 1, 2, 5, 10, or up to 15) coherent planar layers of graphene disposed in the metal lattice. Figures 21C and 27C show an exemplary cross-sectional structure of such a coherent planar layer of graphene disposed along the basal surface of an aluminum matrix according to one embodiment of the inventive concepts described herein. Those skilled in the art will appreciate that various implementations of the powders described herein may include particles exhibiting such cross-sectional structures. In practice, when incorporated into the lattice, carbon is advantageously wicked to the basal surface rather than precipitated at grain boundaries (or other lattice surfaces). This process is possible solely due to the wettability of graphene at the nanoscale and is not observed when producing carbon-implanted materials using conventional techniques.

[0143] In various aspects, at least some carbon atoms of one or more coherent planar layers of graphene are arranged in interstitial positions within the metal lattice, preferably with one or more coherent planar layers of graphene juxtaposed parallel to the basal planes of the metal lattice. In some embodiments, one or more coherent planar layers of graphene are juxtaposed interstitially between the basal planes of the metal lattice. In some embodiments, one or more coherent planar layers of graphene are interstitially interdigitated between the basal planes of the metal lattice. Those skilled in the art reading this disclosure will appreciate that this unique distribution of carbon in interstitial positions and arrangement relative to the basal planes of the lattice is possible due to the inventive process described herein. This inventive process takes advantage of the high "wettability" of graphene (particularly pure graphene) at the nanoscale, as described herein, allowing for high carbon loading, substantially uniform carbon dispersion, and a substantial absence of carbon aggregates and / or agglomerates, all of which cannot be achieved using conventional techniques. See, for example, Figures 1A-1B for a graphical comparison of conventionally produced "Covetic materials" versus materials produced using the inventive techniques described herein, and the corresponding description below.

[0144] Continuing with reference to powder materials according to the present disclosure, at least a portion of the carbon atoms can be covalently bonded to metal atoms of the metal lattice, simultaneously allowing for non-polar covalent bonds between carbon atoms and / or metallic bonds between metal atoms of the material. More specifically, non-polar covalent bonds between carbon atoms and / or between carbon atoms and metal atoms are characterized by equal sharing of electrons between the bonded atoms, as opposed to polar covalent bonds (where electrons are shared between the bonded atoms) or ionic bonds (where the bonded atoms are bonded due to a charge difference after the transfer of electron(s) from one atom to the other). In some embodiments, particles of the powder material can substantially or completely eliminate polar covalent bonds and / or ionic bonds. In this context, "substantial" elimination of polar covalent bonds and / or ionic bonds refers to compositions whose properties (e.g., crystal structure, mechanical strength, thermal / electrical conductivity, reflectivity, etc., as described below, particularly with reference to FIG. 29) are not caused by the presence of polar covalent bonds and / or ionic bonds. Compositions that substantially exclude polar covalent and / or ionic bonds can be considered to consist essentially or entirely of non-polar covalent bonds, at least with respect to the carbon and metal atoms bonded within the structure.

[0145] Furthermore, as will be understood by those of skill in the art upon reading this disclosure, the graphene is preferably "pure" in that the 2D or 3D structure is substantially free of defects such as voids, inclusions, contaminants, etc.

[0146] The metal grid may include one or more metals, such as aluminum, copper, iron, nickel, titanium, tantalum, tungsten, chromium, molybdenum, cobalt, manganese, niobium, and combinations thereof. When a combination is included, the metal is preferably in the form of an alloy, such as an Inconel alloy, preferably an Inconel formed from nickel, chromium, aluminum, copper, iron, titanium, tantalum, molybdenum, cobalt, manganese, and / or niobium, most preferably an Inconel superalloy such as Inconel 600, Inconel 617, Inconel 625, Inconel 690, Inconel 718, Inconel X-750, or a combination thereof. In some cases, the combination includes tin and / or tungsten, and / or silver, and / or antimony, alone or in combination. In some embodiments, one or more of the aforementioned metals can be used alone or in combination as a surfactant to improve the wettability of the metal-carbon combination.

[0147] The powder materials described herein are preferably formed using non-equilibrium plasma, such as may be generated using the microwave plasma-based reactor described herein. The microwave plasma-based reactor process of the present disclosure provides a reaction and processing environment in which gas-solid reactions can be controlled under non-equilibrium conditions (refers to a physical system that is not in thermodynamic equilibrium but can be described by variables that represent an extrapolation of the variables used to specify the system at thermodynamic equilibrium; non-equilibrium thermodynamics pertains to transport processes and chemical reaction rates, as well as the initial melting of metal powders, which can be independently controlled by ionization potential and momentum and thermal energy).

[0148] After in situ nucleation (referring to a fixed location within a reactor or reaction chamber), solid, substantially solid, or semi-solid carbon-based particles emitted from the plasma torch can be deposited layer-by-layer onto a temperature-controlled substrate (such as a drum). The emitted particles can be thermally sprayed onto and bonded to or within a specific substrate. In some cases, no substrate is used; rather, groups of emitted semi-solid particles form one or more directionally organized, freestanding, self-supporting structures. Unlike standard plasma torches, which are limited in their operating flow, power, and configuration, the microwave plasma torch of the present disclosure includes control mechanisms (e.g., flow control, power control, temperature control) for independently controlling one or more constituent material temperatures and gas-solid reaction chemistries, advantageously producing unique, elegant, and highly organized covalently bonded carbon-metal structures with an extremely high degree of uniformity.

[0149] To illustrate, the maximum distinguishable feature size of a uniformly dispersed metal-carbon combination, e.g., as defined by the length measured along the longitudinal axis of the "feature" in question, according to various implementations, is in the range of about 0.01 nanometer (nm) to 1 micrometer (μm), preferably in the range of about 0.01 nm to about 1 μm, more preferably in the range of about 0.01 nm to about 750 nm, even more preferably in the range of about 0.01 nm to about 500 nm, still more preferably in the range of about 0.01 nm to about 100 nm, even more preferably in the range of about 0.01 nm to about 50 nm, and most preferably in the range of about 0.01 nm to about 10 nm. This is in contrast to a non-uniform dispersion, which is characterized by relatively large feature sizes of several (e.g., 3-5) micrometers or more.

[0150] The composition may also include a plurality of "aggregates" and / or a plurality of "aggregates," each of which includes a number of particles bonded together, and each of which includes a number of aggregates bonded together. In some implementations, each of the particles may have a major dimension between 20 nm and 150 nm. Each of the aggregates may have a major dimension between 40 nm and 10 μm. Each of the aggregates may have a major dimension between 0.1 μm and 1,000 μm.

[0151] The covetic materials produced by the disclosed MW reactor-based technology offer various competitive advantages not available in current materials or products. One such advantage relates to the inherent scalability and versatility to formulate unique, physically and chemically stable, and versatile metal-carbon composites that exhibit predictable deformation (referring to stress, strain, elasticity, or some other identifiable physical characteristic) in a variety of configurations and / or structures, including (but not limited to): (1) dense thin film implants, (2) coatings, (3) thick strips, and (4) powder particles that can be subsequently remelted and integrally molded and / or used to form engineered metal alloy components. Any and all of the aforementioned dense thin film MW-reactor-produced carbon-based metal composite implants and / or coatings and / or strips and / or powder particles exhibit enhanced physical, chemical, and electrical properties compared to existing parent metal alloy formulations.

[0152] Materials produced using powders (and / or pellets formed from such powders) as described herein above share many of the same advantageous physical characteristics and properties of the powders themselves, with the exception that macroscale materials may not exhibit the presence of carbon in coherent, planar layer(s) disposed along the basal surface of the metal lattice. Instead, macroscale materials (e.g., produced by microwave plasma spray torches or other suitable techniques described herein (and their equivalents as would be understood by those skilled in the art upon reading such descriptions)) are characterized by previously unattainable carbon loadings (e.g., 1.5% to 90% by weight, and any amount therebetween), uniform / heterogeneous distribution of carbon throughout the metal matrix, and the absence of carbon aggregates and / or agglomerates at the lattice surface(s) (e.g., grain boundaries). Beyond this distinction, final products produced using powder materials, preferably powder covetic materials, may exhibit any one or more physical characteristics and / or properties of the powder precursors in any combination without departing from the scope of the inventive concepts described herein.

[0153] General embodiment According to one general aspect, a composition includes one or more particles, each particle independently comprising a metal lattice having one or more coherent planar layers of graphene disposed within the metal lattice.

[0154] According to another general aspect, a composition includes an Inconel alloy, the Inconel alloy having carbon disposed in a metal lattice of the Inconel alloy.

[0155] According to yet another general aspect, a composition includes a metal lattice, the metal lattice having at least about 15% by weight carbon disposed in the metal lattice.

[0156] Additionally, in various implementations, the aforementioned aspects may include any of the following physical and / or structural features and related characteristics: Furthermore, these features and / or characteristics may be included in different combinations or orders according to different embodiments, without limitation.

[0157] In one aspect, the composition comprises one or more particles, each particle independently comprising a metal lattice, the metal lattice having one or more coherent planar layers of graphene disposed therein. Preferably, at least some of the carbon atoms of the one or more coherent planar layers of graphene are disposed in interstitial positions within the metal lattice. More preferably, the one or more coherent planar layers of graphene are interstitially interdigitated between the basal planes of the metal lattice. The graphene can exist as a single layer (e.g., "single-layer graphene" or "SLG") or as multiple layers (e.g., 2, 3, 5, 10, or any number up to 15 layers (also referred to herein as "few-layer graphene" or "FLG")). At least some of the carbon atoms of one or more layers of graphene are covalently bonded to metal atoms of the metal lattice, and the covalent bond between the carbon atoms and the metal atoms is or includes a nonpolar covalent bond. In some embodiments, the covalent bond can consist essentially or entirely of a nonpolar covalent bond. Similarly, carbon atoms in one or more layers of graphene can be covalently bonded to other carbon atoms in one or more layers of graphene, and these covalent bonds can comprise, consist essentially of, or consist entirely of non-polar covalent bonds, according to different implementations. Thus, one or more particles can substantially or completely exclude polar covalent bonds. Similarly, the metal lattice of each particle can substantially or completely exclude ionic bonds. Each of the one or more layers of graphene is preferably substantially defect-free, such that the graphene is "pure." Preferably, each particle is also characterized by a substantial, or more preferably complete, absence of carbon aggregate(s) and / or agglomerate(s) at the grain boundaries and / or surface(s) of the metal lattice. The inventive processing techniques described herein result in particle(s) with total carbon loadings ranging from about 15% to about 90% by weight, with various intermediate loadings also demonstrated (e.g., in various implementations, about 20%, about 25%, about 33%, about 40%, about 50%, about 60%, about 75%, or up to 90% by weight). Additionally, the particles may be characterized by having a diameter ranging from about 20 nm to about 3.5 μm and / or a maximum distinguishable feature size ranging from about 0.1 nm to about 1 μm.In some implementations, the particles can be compressed into a pellet.

[0158] According to another aspect, a composition includes an Inconel alloy having carbon disposed in its metal lattice. Preferably, at least a portion of the carbon is disposed in interstitial sites of the metal lattice, and more preferably, the carbon is substantially uniformly distributed throughout the metal lattice. Furthermore, in some implementations, the grain boundaries of the composition and / or the surfaces of the metal lattice are substantially free of carbon aggregate(s) and / or agglomerate(s). Thus, the maximum distinguishable feature size of the composition may range from about 0.1 nm to about 1 μm. At least some of the carbon atoms are covalently bonded to metal atoms of the metal lattice, and the covalent bonds between the carbon atoms and the metal atoms are or include nonpolar covalent bonds. In some embodiments, the covalent bonds may consist essentially or entirely of nonpolar covalent bonds. Similarly, carbon atoms can be covalently bonded to other carbon atoms, and these covalent bonds may include, consist essentially of, or consist entirely of nonpolar covalent bonds, according to different implementations. Thus, one or more compositions may substantially or completely exclude polar covalent bonds. Similarly, the metal lattice may substantially or completely exclude ionic bonds.

[0159] According to yet another aspect, the composition includes a metal lattice having at least about 15% by weight of carbon disposed therein. Preferably, at least a portion of the carbon is disposed in interstitial sites of the metal lattice, and more preferably, the carbon is substantially uniformly distributed throughout the metal lattice. Furthermore, in some implementations, the grain boundaries of the composition and / or the surfaces of the metal lattice are substantially free of carbon aggregate(s) and / or agglomerate(s). Thus, the maximum distinguishable feature size of the composition may range from about 0.1 nm to about 1 μm. At least some of the carbon atoms are covalently bonded to metal atoms of the metal lattice, and the covalent bonds between the carbon atoms and the metal atoms are or include nonpolar covalent bonds. In some embodiments, the covalent bonds may consist essentially or entirely of nonpolar covalent bonds. Similarly, carbon atoms can be covalently bonded to other carbon atoms, and these covalent bonds may include, consist essentially of, or consist entirely of nonpolar covalent bonds, according to different implementations. Thus, one or more compositions may substantially or completely exclude polar covalent bonds. Similarly, the metal lattice may substantially or completely exclude ionic bonds.

[0160] In various implementations of the aforementioned aspects, the metal lattice can include one or more metals selected from the group consisting of aluminum, copper, iron, nickel, titanium, tantalum, tungsten, chromium, molybdenum, cobalt, manganese, niobium, and combinations thereof. Accordingly, the metal lattice can be characterized by a crystal structure such as face-centered cubic (FCC), body-centered cubic (BCC), or hexagonal close-packed (HCC). Furthermore, the metal lattice can include carbon in the range of about 15% to about 90% by weight (e.g., about 20%, about 25%, about 33%, about 40%, about 50%, about 60%, about 75%, or up to 90% by weight in various implementations). Carbon is preferably present in interstitial sites of the metal lattice. In some approaches, the metal(s) can be present in the form of an alloy(s). For example, in a particularly preferred approach, the metal is present in the form of one or more Inconel alloys, such as Inconel 600, Inconel 617, Inconel 625, Inconel 690, Inconel 718, and / or Inconel X-750. Even more preferably, the Inconel alloy(s) are superalloy(s).

[0161] overview The disclosure herein describes the integration of low-dosage nanofiller carbon-based materials, such as graphene, known for its unique structural features, such as its high aspect ratio and "2D" planar geometry, with metals. Graphene possesses surprisingly favorable mechanical, physical, thermal, and electrical properties due to its in-plane sp2 C=C bonds (resulting in its 2D planar geometry). Therefore, graphene may serve as an ideal reinforcement for metal-matrix composites compared to alternatives such as microfiller polyacrylonitrile (PAN)-based carbon fibers. Note that even at low graphene nanoplatelet contents (loadings), 3D networks with anisotropy (referring to an object or substance having physical properties that have different values ​​when measured in different directions) are formed, resulting in significantly improved thermal and electrical conductivity, as well as mechanical properties.

[0162] Challenges encountered when using carbon nanofillers in metal matrix composites include difficulty in dispersion due to poor wettability (the ability of a liquid and a solid surface to maintain contact due to intermolecular interactions when they come into contact; the degree of wettability is called wettability and is determined by the balance of forces between adhesive and cohesive forces). The increased surface area provided by nanofillers causes the particles to form clusters and twist due to van der Waals forces between carbon atoms. Clustering of nanofillers within metal matrix composites can lead to undesirable crack and pore formation, which ultimately compromises the structural integrity of the resulting material and can lead to premature failure under high loads or performance conditions.

[0163] Although many processing approaches, such as traditional powder metallurgy, hot rolling, casting, and additive manufacturing, have been (and may still be) used to produce metal matrix composites, achieving uniform dispersion of nanofillers remains a challenge. Damage to the nanofillers due to applied stresses during consolidation, and undesirable or uncontrollable chemical reactions with the matrix at high temperatures during sintering and casting, are some examples of challenges faced in attempts to achieve nanofiller dispersion.

[0164] The defect-free basal plane of graphene exhibits superior and favorable chemical stability compared to the sides and edges of graphene sheets, and graphene sheets may be more likely to interact with metals to form carbides (thermodynamically favorable in terms of Gibbs free energy). However, during processing, defects can easily form on the basal plane, leading to adverse effects on carbide formation and composite properties. Therefore, relatively harsh processing conditions, such as high temperature and pressure, can adversely affect the quality of the interface between carbon nanofillers and their surrounding metal-based matrix. Specifically, high temperature and pressure can adversely affect wetting ability, structural integrity, undesirably affect carbide formation, or otherwise cause other adverse interfacial reactions.

[0165] An alternative process called Covetic (mentioned above) has been successfully used to incorporate carbon nanofillers into metal matrices. Covetic-related processes have been shown to form networks of graphene "ribbons" and nanoparticles within liquid metals using an applied electric field, which exhibit exceptional stability within the metal matrix, even after remelting. Accordingly, the composite structure conducts heat and electricity more efficiently than the parent metal.

[0166] Uniform distribution Because one of the challenges in incorporating graphene into a metal matrix is ​​achieving uniform dispersion, the Cobetic process overcomes this issue through simultaneous exfoliation and wettability of graphene ribbons and / or particles in an applied electric field (either from the carbon electrode or from the decomposition of the carbon additive). Impurities such as oxygen and hydrogen can be managed by redox reactions at the particle surface, assuming an appropriate induced voltage at that surface, promoting wettability / dispersion. The challenge is one of controlling the structural integrity and uniformity (e.g., uniformity in terms of size, defects, etc.) of the graphene ribbons and / or particles, as well as their chemical reactivity with the metal at high temperatures, and the distribution of the particles in the bulk and at the surface of the melt.

[0167] More Complexity The fundamental modes of energy conduction in metals (both thermal and electrical) are electronic (at least in part) and controlled by the degree of crystallinity and impurities, but for fillers like graphene to improve the thermal conductivity of metal-matrix composites (conduction in graphene is via phonons), some degree of registry and / or coherency with the metal lattice (e.g., integrally bonded nanoscale carbon) (also additionally or alternatively referred to as a scaffold, matrix, or structure) is required, or a threshold of minimum platelet spacing (e.g., proximity or network) for conduction between platelets is required (e.g., graphene needs to be single-layer or just a few layers and tens of nanometers in length). However, for reinforcement of metal matrices, graphene may need to be chemically (or in some cases even physically) bonded to the matrix for adequate load transfer (note that graphene lengths can be greater than about 0.5 μm for maximum load transfer). Apart from solid solution strengthening (which relies on coherent and / or semi-coherent elastic strain between carbon (graphene) nanofillers and the metal lattice), individual graphene nanoparticles can act as barriers to the accumulation or pinning of dislocations at grain boundaries (Hall-Petch grain refinement, etc.), which refers to a method of strengthening materials by changing the average crystallite (grain) size. It is based on the observation that grain boundaries are insurmountable boundaries for dislocations, and that the number of dislocations within a grain affects the stress accumulation in neighboring grains, ultimately activating dislocation sources and thus enabling the deformation of neighboring grains as well. Therefore, by changing the grain size, it is possible to affect the number of dislocations accumulated at grain boundaries and the yield strength, both of which improve mechanical properties.

[0168] Again, due to its 2D nature and high surface area, graphene can orient along grain boundary regions in addition to aligning along slip planes within the metal structure. Whether the property of interest is chemical, mechanical, thermal, or electrical, the greater the alignment and registry (at the atomic level) of the nanofiller with the crystalline structure of the surrounding metal matrix, the greater the property enhancement and stability in the metal matrix composite structure.

[0169] Fundamentally, the growth of carbon on a metal surface (heterogeneous) or its precipitation from solution in the melt (homogeneous) depends on the solubility of carbon in the metal (according to the binary phase diagram shown on the right side of Figure 10). The solubility of carbon in pure transition metals (and many pure metals in general) is very low, e.g., near the melting point of the metal, but increases as the temperature rises well above the melting point (e.g., up to 2,000°C or more). The solubility of carbon in nickel, e.g., near the hypereutectic point of about 2.5%, is one of the higher solubilities of carbon in pure metals. Note that the addition of interstitial impurities, e.g., oxygen, boron, nitrogen, or substitutional atoms to a metal, can affect (e.g., potentially increase) the solubility of carbon. It has been shown that the higher the solubility of carbon in a metal or the higher the temperature of the molten metal, the greater the thickness of carbon that precipitates on the metal's surface as it cools and solidifies. An important point to note is that the solubility of carbon is higher near the free surface, which, combined with the interfacial energy of the liquid-air interface, promotes the precipitation of solid carbon at the metal melt-air interface. Equipment and techniques for operating the equipment to overcome the problems associated with this phenomenon are addressed in conjunction with the figures and corresponding discussion.

[0170] Definition and Use of Drawings Some of the terms used in this description are defined below for ease of reference. The presented terms and their respective definitions are not intended to be strictly limited to these definitions, and terms may be further defined by the use of the term within this disclosure. The term "exemplary" is used herein to mean serving as an example, instance, or illustration. Any aspect or design described herein as "exemplary" should not necessarily be construed as preferred or advantageous over other aspects or designs. Rather, use of the word exemplary is intended to present concepts in a concrete manner. As used in this application and the appended claims, "or" is intended to mean an inclusive "or" rather than an exclusive "or." That is, unless otherwise specified or clear from the context, "X employs A or B" is intended to mean any of the natural inclusive permutations. That is, if X employs A, if X employs B, or if X employs both A and B, then "X employs A or B" is satisfied under any of the foregoing cases. As used herein, at least one of A or B means at least one of A, or at least one of B, or at least one of both A and B. In other words, the phrase is disjunctive. Furthermore, the articles "a" and "an," as used in this specification and the appended claims, should be construed generally to mean "one or more" unless otherwise specified or unless the context clearly indicates a reference to the singular form.

[0171] Various implementations are described herein with reference to the drawings. It should be noted that the drawings are not necessarily drawn to scale, and that elements of similar structure or function may generally be designated by similar reference characters throughout the drawings. It should also be noted that the drawings are intended only to facilitate description of the disclosed implementations, and do not represent an exhaustive treatment of all possible implementations, nor are they intended to pose any limitations on the scope of the claims. Furthermore, the implementations shown need not represent all aspects or advantages of use in any particular environment.

[0172] Aspects or advantages described in connection with a particular implementation are not necessarily limited to that implementation and may be implemented in any other implementations, even if not so indicated. References throughout this specification to "some implementations" or "other implementations" refer to particular features, structures, materials, or characteristics that are described in connection with the implementations as being included in at least one implementation. Thus, the appearances of the phrase "in some implementations" or "in other implementations" in various places throughout this specification do not necessarily refer to the same implementation or multiple implementations. The disclosed implementations are not intended to limit the scope of the claims.

[0173] Description of an Exemplary Implementation FIG. 1A is a comparative chart 1A00 showing two different Cobetic material forming techniques 102 and examples of materials resulting from each application.

[0174] In conventional metal smelting methods for producing covetic materials, solid carbon is added to a metal melt. This conventional metal smelting technique is governed by the kinetics of carbide formation and interdiffusion across a solid-liquid (e.g., carbon-metal) interface under an applied electric current, which provides additional energy to overcome stacking fault energy between carbon and metal atoms. Therefore, conventional metal smelting techniques for forming covetic processes are not significantly different from other composite processing methods, such as powder metallurgy and / or hot rolling, which involve the integration of second-phase particles into a metal matrix. These conventional composite methods face many challenges related to dispersion and / or distribution, reactivity, and variability of material properties. Furthermore, conventional covetic processes rely on batch processing, which often results in inconsistent conversion yields and large variations in resulting properties.

[0175] As shown by image 105, when using conventional metal melting methods 103, the resulting material contains substantial carbon aggregates and / or agglomerates, particularly at the grain boundaries and / or surfaces of the metal lattice. This in turn (1) limits the role of carbon in reinforcing the lattice and (2) limits the tunability of the surface morphology for surface functionalization. By comparison, when using the techniques of the present disclosure, the resulting material exhibits near-uniform homogeneity (e.g., no or substantially no aggregates and / or agglomerates, particularly at the grain boundaries and / or lattice surfaces), which results from the uniform dispersion of carbon within the lattice. This is shown in homogeneity image 106.

[0176] Covetic materials, as shown in the homogeneity image 106, are characterized by many desirable material properties 108, such as uniformity, high carbon loading, and low carbon content at the surface. These are highly desirable material properties that are not exhibited by materials formed using conventional metal smelting methods 103. Therefore, what is needed is an improved approach that overcomes the shortcomings of conventional metal smelting methods 103.

[0177] One such improved approach involves a plasma spray torch method 104. The application of the plasma spray torch method results in a consistent yield of covetic material, thus overcoming the yield shortcomings of conventional metal smelting methods. Furthermore, the application of the plasma spray torch method results in covetic material having the aforementioned improved mechanical, thermal, and electrical properties, thus overcoming the material shortcomings of conventional metal smelting methods.

[0178] An improved approach As shown, the plasma spray torch method 104 can be configured to use an introduced input material (referring to providing a gaseous carbon-containing feedstock species, such as methane, and exciting it, such as through the application of MW energy directed through the methane gas). However, by dissociating the carbon-containing gas (such as methane or other hydrocarbon sources) at high temperatures, self-limiting monolayers of carbon, specifically pure graphene, can be grown on and / or within a metal (such as copper, gold, zinc, tin, or lead) lattice. The number of monolayers depends, at least in part, on the solubility of carbon in the metal. The growth rate, bonding, and final structure of graphene films on metal substrates depend on the valence electrons and symmetry (close-packed planes) of the metal. Similarly, metals can be grown on carbon and can preferentially nucleate and grow at defect sites or selective oxygen- or hydrogen-terminated sites in the carbon. Fabricating alternating monolayer carbon and metal stacks can achieve enhanced properties of graphene-reinforced metal composite structures.

[0179] Using a microwave plasma reactor, pure 3D few-layer graphene particles can be continuously nucleated and grown from a hydrocarbon gas source. Furthermore, by adding selected elements to the plasma gas stream, the elements can be incorporated into the 3D graphene particle scaffold. The microwave plasma reactor process provides a unique reaction environment in which gas-solid reactions can be controlled under non-equilibrium conditions (e.g., chemical reactions can be independently controlled by ionization potential and momentum, as well as thermal energy). Reactants can be inserted into the plasma reactor zone as solids, liquids, or gases, allowing for independent control of the nucleation and growth rates of unique non-equilibrium structures (e.g., graphene on metal or metal on graphene).

[0180] For example, to fabricate nanometer-scale integrated graphene-metal composites, fine nanometer-scale metal particles can be introduced into a microwave plasma torch along with a hydrocarbon gas such as methane. The methane dissociates into hydrogen and carbon (e.g., forming C and C2 using the ideal energy of the microwave plasma), which can then nucleate and grow ordered graphene on the semi-molten surface of the metal particles. By adjusting the process conditions to independently control the temperature of the metal relative to the reactivity and delivery of carbon to the metal surface, non-equilibrium energy conditions can be created. Ionized hydrogen (or other ions) at controlled low energies can be used to bombard / sputter the surface of the growing graphene-metal surface without damaging the structure of the graphene-metal composite. This, in turn, promotes the further growth of alternating layers of graphene and metal. Furthermore, depending on the residence time and energy within the plasma reaction zone, metal-graphene structures with specific properties can be fabricated, and these properties are retained even when the metal-graphene structures are rapidly cooled after being sprayed onto a substrate at controlled temperatures. Formation of metal-graphene structures at controlled energies in the plasma and control of the substrate temperature independently controls the energy conditions throughout the evolution of these cobetic materials.

[0181] Graphene can be applied (and / or deposited) onto metal or metal-containing layers of material by "sputtering." (Sputtering refers to the expulsion of fine particles of solid material from the surface of the material after the material itself has been bombarded by energetic particles of a plasma or gas. Because sputtering can affect extremely fine layers of material, it is frequently used in science and industry to perform precision etching, analytical techniques, and the deposition of thin film layers in the manufacture of optical coatings, semiconductor devices, and nanotechnology products.) Such sputtering, as described above, can be controlled when used with the MW plasma reactors discussed herein by controlling the residence time and energy within the plasma reaction zone to promote the growth of alternating layers of graphene and metal. These alternating layers of graphene and metal are organized into coherent planes of regularly (e.g., crystallographically) arranged atoms. This crystallographic arrangement is preserved when the graphene-metal layer is rapidly quenched onto a cooler substrate. (In materials science, quenching, or rapid / fast quenching, refers to the controlled, rapid cooling of a workpiece in water, oil, or air to obtain specific material properties. Quenching prevents or controls undesirable low-temperature processes, such as phase transformations, by reducing the time window during which these undesirable reactions are thermodynamically favorable and kinetically accessible. For example, quenching can reduce the grain size and increase the hardness of both metal and plastic materials.) Rapid quenching, as described above, helps essentially "freeze" (refers to retention in a substantially solid state, not just the traditional definition of a liquid-to-solid phase change) the graphene into the metal in the desired crystallographic arrangement formed in the plasma reactor. The internal and surface homogeneity of the resulting material is extremely uniform. This extremely uniform homogeneity can be used to distinguish it from materials formed using metal melting methods 104. This is because the metal melting method 104 does not allow for control of ion energy independent of thermal energy.More specifically, because the metal fusion method 104 cannot achieve the desired higher ion energies independent of thermal energy, the temperature within the metal fusion reaction chamber may be too high to organize the graphene-metal layer into coherent planes of atoms in the desired crystallographic arrangement.

[0182] Thus, when using the metal smelting method 104, the desired crystallographic arrangement of the graphene-metal never occurs, and therefore, the graphene-metal layer fails to retain the desired crystallographic arrangement when quenched onto a low-temperature substrate. Instead, when using the metal smelting method 104, undesirable carbon deposition occurs (e.g., carbon deposition from the melt), which in turn leads to the undesirable formation of aggregates and / or agglomerates, resulting in non-uniformity in the resulting composition. This non-uniformity in the resulting composition can result in less-than-ideal chemical and / or physical (mechanical) characteristics in the resulting composition, including, but not limited to, premature mechanical failure.

[0183] Figure 1B shows a high-resolution transmission electron microscope image 114 and a high-resolution energy dispersive spectroscopy x-ray image 116. Also shown here for convenience is the homogeneity image 106 of Figure 1A.

[0184] As shown in this exemplary set of images, carbon is uniformly distributed throughout the metal lattice. This is highlighted in the high-resolution transmission electron microscope image 114. Furthermore, the extremely high carbon loading within the metal lattice is clearly shown by the high-resolution energy dispersive spectroscopy x-ray image 116. In this example, the carbon loading forms approximately 60% of the total copper-carbon lattice. This is shown in the high-resolution energy dispersive spectroscopy x-ray image 116. In this particular image, the dark areas are carbon and the lighter areas (visible as dots) are copper.

[0185] As can be seen from the images, and particularly from the pattern in the high-resolution energy dispersive spectroscopy x-ray image 116, the carbon and parent metal (e.g., copper in this case) are uniformly dispersed. As shown, this uniform lattice-level dispersion exists at the surface, and furthermore, this uniform lattice-level dispersion also exists deep within the parent metal. Additional images of the Cobetic material are shown in Figures 20A1, 20A2, and 20B, which are followed by a discussion of (1) the material evolution process, (2) the plasma spray torch apparatus, and (3) various configurations of the plasma spray torch.

[0186] In one use scenario, the covetic material in Figure 1B can be fabricated using a tunable microwave plasma torch that produces integrated graphene-metal composite films at high speed and in large quantities. We next briefly consider one particular fabrication process in which graphene is grown on small molten metal particles.

[0187] 2 depicts a manufacturing process 200 for growing graphene on small molten particles. Optionally, one or more variations of manufacturing process 200, or any aspect thereof, may be implemented in terms of the architecture and functionality of the implementations described herein. Manufacturing process 200, or any aspect thereof, may be implemented in any environment.

[0188] One envisioned method is to use a "non-equilibrium energy" microwave plasma torch to provide non-equilibrium control over the temperature of the metal independent of carbon production. This plasma torch energy is then directed at the surface of molten and / or semi-molten metal particles. This technique allows time for growth to occur in the melt. Growth in the melt (or semi-molten or core-shell material) created within the torch flows through the main plasma plume to the surface of the growing metal and is then rapidly quenched. This technique provides a means to grow thick films that, once layered, can be grown into uniformly thick ingots and / or grown into or on component parts that can be post-machined or remelted depending on the application.

[0189] Additionally, Figure 2 is presented to demonstrate the effect of independently controlling the temperature and gas-solid reaction chemistry of the constituent materials when growing graphene on small molten particles. Figure 2 shows the evolution through several processes of cobetic material fabrication and presents the process used in the formation of plasma torch-based cobetic materials.

[0190] As shown, semi-solid particles emitted from the plasma torch can be deposited in a layer-by-layer manner onto a temperature-controlled substrate. Unlike standard plasma torches, which have limited control over operational flow, as well as power and other configurations, the contemplated microwave plasma torch can be operated to independently control component material temperature and gas-solid reaction chemistry.

[0191] As can be seen from the above disclosure, microwave plasma sources can result in (for example): (1) higher plasma density, (2) narrower ion energy distributions, and (3) improved coating properties. This is at least partially due to improved power coupling and absorption at 2.45 GHz. Typical electron temperatures, depending on pressure, are on the order of 1 eV to 15 eV, resulting in plasma densities of >10 cm. Such low electron temperatures are advantageous not only in terms of controlling plasma chemistry but also in limiting ion energy (argon-based coaxial microwave plasmas typically have ion energies in the range of 5 eV to 80 eV). As a result of the narrow plasma sheath formed using these high-density plasmas, collisional broadening of the ion energy distribution is prevented, thereby resulting in a well-defined ion energy distribution that supports fine control of specific thin film deposition processes. Furthermore, the use of pulsed power in microwave plasmas allows for the creation and control of non-equilibrium energy. During the application of microwave energy, power is delivered throughout the volume in which the plasma is formed, thus accumulating energy in a stepwise collisional energy regime.

[0192] The foregoing discussion of FIG. 2 includes techniques for applying microwave energy power, which are disclosed in further detail below.

[0193] FIG. 3 shows a plasma energy state chart 300 illustrating how a pulsed microwave energy source can be used to grow graphene on small molten particles.

[0194] Microwave plasma sources have the potential to achieve higher plasma densities, narrower ion energy distributions, and improved coating properties as a result of improved power coupling and absorption at 2.45 GHz. Typical electron temperatures, depending on pressure, are on the order of 1 eV–15 eV, resulting in plasma densities of >10 cm. Such low electron temperatures are advantageous not only in terms of controlling plasma chemistry but also in limiting ion energy (argon-based coaxial microwave plasmas typically have ion energies in the range of 5 eV–80 eV). As a result of the narrow plasma sheath formed using these high-density plasmas, collisional broadening of the ion energy distribution is prevented, resulting in a well-defined ion energy distribution, which is necessary for fine control of some thin film deposition processes. Furthermore, the use of pulsed power delivered to microwave reactors allows for the creation and control of non-equilibrium plasma energy. During the application of microwave energy, power is delivered into the volume where the plasma is formed, thus depositing energy in a stepwise collisional energy regime.

[0195] Once the initial plasma forms in most of the volume, the delivery antenna where the energy is greatest continues to increase in a highly localized manner. The plasma density in the vicinity decreases slightly until the plasma contracts. Further details regarding general approaches for creating and using pulsed microwave energy sources are described in U.S. Patent Publication No. 10,332,726, published June 25, 2019, which is incorporated herein by reference in its entirety.

[0196] Figure 3 shows that the initial energy of the plasma is much higher in a non-equilibrium state until it contracts at a much lower stable temperature. More specifically, the plasma energy state chart depicts the transition from an initial high-energy non-equilibrium state to a low-energy stable equilibrium state. Once the initial plasma is formed, the delivery antenna, where energy is maximized, continues to increase in a highly localized manner until energy shielding causes the plasma to contract and be lost to the rest of the chamber.

[0197] The pulsed microwave energy source can be controlled to optimize the electron temperature for growing graphene on small molten particles. This is particularly effective at pressures of >>20 Torr. The chamber environment must be controlled to ensure that the plasma chemical dissociation is uniform and that the coating of material is similarly uniform.

[0198] As shown in Figure 3, the energy profile shows that the initial energy is high and then contracts to a lower level after a period of time, remaining at that level until power is removed. The plasma extinguishes, re-starts, and then follows the energy cycle again. By reducing the time from initial plasma ignition to stabilization, the plasma remains primarily within the bulk of the system, where more uniform dissociation of material may occur. Reducing the time from initial plasma ignition to stabilization can be achieved by controlling the frequency and duty cycle of the pulses.

[0199] One technique for controlling electron temperature in a pulsed microwave reactor is shown and described with reference to FIG.

[0200] 4 illustrates an electronic temperature control technique 400 used to grow graphene on small molten particles. Optionally, one or more variations of the electronic temperature control technique 400, or any aspect thereof, may be implemented in terms of the architecture and functionality of the implementations described herein. The electronic temperature control technique 400, or any aspect thereof, may be implemented in any environment.

[0201] Figure 4 illustrates an embodiment related to growing few layers of graphene on molten nanoscale-sized particles rather than incorporating carbon into the bulk of the molten slurry. Specifically, this figure is presented with respect to its contribution to controlling plasma temperature via controlling microwave pulse frequency.

[0202] Plasma temperature control via pulse frequency control As shown in Figure 3 above, the energy profile shows that the initial energy is high and then after a period of time contracts to a lower level where it remains until power is removed. The plasma extinguishes, regenerates, and then follows the energy cycle again. By shortening the time from initial plasma ignition to stabilization, the plasma remains primarily within the bulk of the system, where more uniform dissociation of materials may occur.

[0203] As shown in Figure 4, the effect is substantially dependent on the timing of the on / off cycle of the microwave energy source. By controlling the frequency of the pulses, optimal chemical dissociation and uniform coating can occur. Furthermore, by setting the pulse frequency, the average temperature of the plasma can be controlled as well.

[0204] Plasma temperature control in microwave plasma torches The integrated microwave plasma torch discussed herein is used to address the formation of integrated second-phase carbon-metal composite structures with improved mechanical, thermal, and electrical properties over existing metal alloys and conventional composite processing methods. Furthermore, the microwave plasma torch can be used to form carbon-metal composite coatings and particles directly on high-value asset components. Furthermore, the aforementioned methods and equipment meet many clean energy goals related to improved electrical power distribution and efficient transformer and heat exchanger performance.

[0205] Practical Applications of Microwave Plasma Torches Using integrated microwave plasma torch technology, materials can be economically (e.g., cost-effectively) deposited and / or formed at high rates and in a variety of different configurations. Beneficiary industries of this technology include various energy production industries, particularly those involved in power transmission and storage, transportation, military equipment, and many other manufacturing industries. As one specific practical application example, the metal surfaces of aircraft can be treated by plasma spraying to create a covetic material at the metal-air interface. In this way, the metal surface becomes resistant to corrosion. Furthermore, the carbon atoms near the surface allow other materials to be chemically bonded to the carbon atoms and / or attached to the surface. The aforementioned other materials that can be chemically bonded to the carbon atoms can be selected based on the requirements arising in various practical applications.

[0206] As another specific example of practical application, metal surfaces on aircraft (planes, helicopters, drones, projectiles, missiles, etc.) can be treated by plasma spraying to produce a Cobetic material coating that acts as an infrared shield (e.g., anti-detection measure).

[0207] 5 shows a dual plasma torch apparatus 500 used to grow graphene on small molten particles. Optionally, one or more variations of the dual plasma torch apparatus 500, or any aspect thereof, may be implemented in terms of the architecture and functionality of the implementations described herein. The dual plasma torch apparatus 500, or any aspect thereof, may be implemented in any environment.

[0208] The equipment setup shown uses: (1) a metal plasma spray torch that delivers molten metal to the surface of a heated substrate (Al, Cu, Ag, etc.), and (2) a microwave plasma torch that delivers ionized carbon and plasma radicals to the molten surface to induce covetic growth on the molten metal.

[0209] The system is inserted into an inert gas environment, or an atmospherically controlled chamber, to better control the oxidation of the material. In one implementation, the setup and operation of the torch of Figure 5 is shown in Table 1, the details of which are discussed below.

[0210] [Table 1]

[0211] Step D1: Identification and selection of reactive materials Any number of metals can be plasma sprayed simultaneously with metastable carbon species to form nanocarbon-metal composite structures. Different metals with high electrical and thermal conductivity can be used when forming 2D graphene at concentrations above their thermodynamic solubility limits. In some cases, two different metals are selected that each have different carbon solubility limits and / or different melting points and / or different densities and / or different crystal structures.

[0212] Step D2: Selection, modification, and validation of microwave and "standard" plasma spray torch(s) The apparatus of Figure 5 can (in one particular implementation) consist of a substantially "standard," off-the-shelf plasma spray and microwave plasma torch. Having two torches allows for two distinct processing steps: (1) initial melting of the metal, and (2) nucleation / growth of graphene platelets from a hydrocarbon source. Each of the two torches can be controlled independently of the other.

[0213] As shown in Figure 5, two torches are juxtaposed for simultaneous or sequential operation. Specifically, microwave plasma with its low electron temperature and high electron density can be used to optimize graphene formation (including nucleation rates at the carbon supersaturation threshold), while a standard plasma spray torch can be used to heat metal powder / particles to a molten or semi-molten state and then accelerate the particles (along with the nucleated ionized carbon / graphene) toward the substrate. The two independent flow streams can be tailored to achieve fine-scale graphene growth on the semi-molten particle surface. In some cases, the dual-torch configuration includes a means to maintain an inert atmosphere (such as a cover gas) in or near the torch discharge stream, as well as in and around the impact region at the surface of the substrate. This configuration is advantageous for minimizing or preferably preventing the inclusion of atmospheric gases (such as oxygen, nitrogen, water vapor, etc., as will be understood by those skilled in the art) in the composition, which can adversely affect the bonding between carbon and metal atoms. Thus, in one particular implementation, the dual torch system is configured to be inserted into a fully controlled inert gas environment (such as a chamber) to effectively control material oxidation.

[0214] Step D3: Rationale and definition of plasma treatment parameters The reactants (e.g., hydrocarbons) and inert gases and flow rates are selected to ensure plasma stability and control of nucleation and growth processes within the plasma (e.g., supersaturation thresholds for a given gas mixture and flow rate). The acceleration rate and temperature of the metastable carbon are controlled during transfer from the plasma to the substrate. Accordingly, the process conditions of a standard plasma spray torch are set to create a monolithic thin film with which the carbon can collide and react. The surface temperature and local gas-phase environment are controlled to promote interaction and growth of the metastable carbon phase.

[0215] Step D4: Dual (Metal and Microwave) Plasma Torch Operation Various parameters of the process window of both the metal and microwave plasma torch are configured to be controlled independently or, in some implementations, in conjunction with one another. The process window for carbon-metal integration formation is characterized before, during, and after operation of one or more of the metal and microwave plasma torch (referred to herein as a "dual plasma torch"). Furthermore, one or more parameters or combinations of parameters are selected, carbon-metal deposition is observed, and the as-deposited sample can be characterized for various distinguishing factors using any technique known in the art, including, but not limited to, morphology (such as using a scanning electron microscope (SEM)), structure (e.g., via X-ray diffraction (XRD) and via Raman spectroscopy), and / or physical and chemical composition.

[0216] 6 shows a pulsed microwave plasma spray torch apparatus 600 that can be tailored to grow graphene on small molten particles. By way of example, one or more variations of the pulsed microwave plasma spray torch apparatus 600 (or any embodiment thereof) may be implemented in terms of the architecture and functionality of the implementations described herein. The pulsed microwave plasma spray torch apparatus 600 (or any embodiment thereof) can be implemented in any environment.

[0217] In this configuration, a transverse-field (TE) microwave energy power means is coupled onto (or, in some implementations, also substantially penetrates) the central dielectric tube, allowing microwave energy to propagate within and throughout the central dielectric tube. The gas supplied to the central region (in this example) can be a hydrocarbon gas such as methane, which absorbs microwave radiation. Metal powder is supplied (carried by a substantially inert carrier gas) and heated within the body (or main chamber) of the pulsed microwave plasma spray torch apparatus 600 from a combination of plasma-derived thermal energy and applied thermal energy. Upon exposure to such energy, the metal powder melts upon reaching a melting temperature, producing a viscous, flowable liquid material, or droplets (potentially including a semi-solid material), or any other possible dispersion (depending primarily on the accompanying melting conditions).

[0218] As the hydrocarbon gas decomposes into its constituent elemental species, carbon radicals nucleate on the exposed surfaces of the molten metal droplet. The combination of microwave energy adjustment settings and thermal plume temperature settings can allow for different temperatures between the melting temperature and the plasma decomposition / ionization temperature in the central region of the pulsed microwave plasma spray torch device 600. Non-equilibrium conditions (referring to temperature, pressure, etc.) within the central chamber or region of the plasma spray torch device can enable (or otherwise promote) the internal lattice arrangement of graphene / carbon, while rapid quenching creates conditions that promote the growth of covalent materials.

[0219] As understood herein, internal lattice configuration refers to the arrangement of a synthesized lattice structure of a carbon material, such as graphene, within the lattice structure of the input metal(s) such that individual carbon and metal atoms are at least partially aligned. For example, internal lattice configuration includes situations in which one or more layers (preferably coherent planar layers) of graphene, such as single-layer graphene (SLG) or few-layer graphene (FLG), are interstitially juxtaposed between the basal planes of the metal lattice and / or interstitially interdigitated between the basal planes of the metal lattice. Internal lattice configuration also includes embodiments in which other carbon-based compounds, such as three-dimensional graphene, carbon nano-onions (CNO), graphene nanoribbons, carbon nanotubes, graphene superlattices, and their equivalents, are interstitially juxtaposed between the basal planes of the metal lattice and / or interstitially interdigitated between the basal planes of the metal lattice, as will be understood by those skilled in the art. Again, regardless of the specific synthesized lattice structure of the carbon-based compound, a key feature of internal lattice configuration is that individual carbon and metal atoms are at least partially aligned. Diagrams showing internal lattices in which the carbon and metal lattices are oriented so that the carbon and metal atoms are at least partially aligned are shown in Figures 8A-B, 12, 26C, and 26D and the corresponding written description below.

[0220] Thus, although internal lattice configuration refers to the spatial arrangement of carbon atoms and metal atoms within the lattice and should be distinguished from chemical and / or ionic bonds, according to various implementations, the compositions of the present invention described herein further include features such as non-polar covalent bonds between individual carbon atoms within the composition and / or non-polar covalent bonds between individual carbon atoms and metal atoms within the composition.

[0221] Preferably, compositions exhibiting an internal lattice configuration are characterized by the substantial absence of polar covalent bonds between individual carbon atoms and between carbon atoms and metal atoms. Even more preferably, the compositions of the invention described herein are characterized by the substantial absence of ionic bonds within the metal lattice.

[0222] As will be appreciated by those skilled in the art, polar covalent bonds, non-polar covalent bonds, ionic bonds, and metallic bonds each have unique identifying characteristics and corresponding electronic and chemical properties.

[0223] Ionic bonds occur after the complete transfer of bonding electrons from one atom to another. The resulting positively and negatively charged ions are electrostatically attracted to each other. Importantly, ionic bonds rarely have a specific directionality because they arise from the electrostatic attraction of each ion to all surrounding ions of the opposite charge. Ionic compounds generally have high melting temperatures, high boiling temperatures, are brittle (low mechanical strength), and can conduct electricity when molten or in aqueous solution.

[0224] In metallic bonding, the bonding electrons are delocalized in the atomic lattice. In metals, each atom contributes one or more electrons that reside among many atomic centers. The free movement of delocalized (or "free") electrons results in important properties such as high electrical and thermal conductivity of metals. In particular, the compositions of the present invention described herein, which have carbon dispersed throughout the metal lattice and substantial covalent bonds between the carbon atoms and metal atoms of the lattice, are characterized by all or substantially all (e.g., at least 90%, at least 95%, at least 98%, at least 99%, etc.) of the electrons participating in such covalent bonds, which can alter the electrical and / or thermal conductivity of the composition.

[0225] While both polar and nonpolar covalent bonds involve the sharing of electrons, compounds containing polar covalent bonds are characterized by unequal sharing of electrons between the bond partners. For example, in hydrogen chloride, the chlorine atom has a higher electronegativity than hydrogen and exhibits a stronger attraction for electrons. Therefore, the "shared" electrons bond more strongly to the chlorine atom, resulting in a partial negative charge on the chlorine and a partial positive charge on the hydrogen (hence, a dipole in the HCl molecule). In water, the bonds between each hydrogen and oxygen atom are similarly characterized due to the oxygen's greater electronegativity. This creates a dipole moment between each hydrogen and oxygen atom, and because of its curved shape, the entire water molecule exhibits an overall dipole. However, not all compounds exhibiting nonpolar covalent bonds exhibit an overall dipole. Tetrachloromethane has four chlorine atoms bonded to the central carbon, evenly spaced from one another. Although each carbon-chlorine covalent bond is nonpolar, the spatial arrangement of the molecule negates the overall bond moment, resulting in a molecule with zero net polarity. Similarly, the linear geometry of carbon dioxide negates the dipole moments exhibited between each oxygen atom and the central carbon, resulting in a molecular structure with no net dipole moment.

[0226] In any case, in the presence of an electric field, the atoms and / or electron clouds involved in the polar covalent bonds may shift, inducing polarization aligned with the electric field. This phenomenon can provide the corresponding compound with energy storage capabilities and contribute to the capacitance of the composition. Compounds exhibiting polar covalent bonds, particularly small molecules or molecules with a large proportion of polar covalent bonds (e.g., at least 10%, at least 20%, at least 25%, at least 50%, etc., in various embodiments), are characterized by melting and boiling temperatures that are lower than compounds exhibiting ionic bonds (again, particularly small compounds and compounds with a large proportion of ionic bonds), but higher than compounds exhibiting non-polar covalent bonds (again, particularly small compounds and compounds with a large proportion of non-polar covalent bonds). Compounds exhibiting polar covalent bonds may or may not exhibit electrical conductivity, but this electrical conductivity is typically lower than that of ionic compounds. Furthermore, compounds that exhibit polar covalent bonds (again, particularly small compounds and compounds that exhibit a high proportion of polar covalent bonds) are moderately soluble in water (solubility depends on the overall polarity of the compound), but are generally not soluble or only nominally soluble in non-polar solvents.

[0227] In contrast, nonpolar covalent bonds are characterized by the equal sharing of electrons between the bond partners, resulting in the absence of a dipole moment between them. Compounds that exhibit exclusively (or substantially exclusively) nonpolar covalent bonds between their constituent atoms therefore lack an overall dipole moment and the corresponding characteristics described herein above, as well as other characteristics that would be understood by one of ordinary skill in the art upon reading this disclosure. Exemplary, non-limiting compounds that exhibit exclusively (or substantially exclusively) nonpolar covalent bonds include graphite, single-layer graphene (SLG), few-layer graphene (FLG), three-dimensional graphene, carbon nano-onions (CNO), graphene nanoribbons, carbon nanotubes (CNTs) (both single-walled (SWCNTs) and multi-walled (MWCNTs)), graphene superlattices, and the like, as described herein, and equivalents thereof, as would be understood by one of ordinary skill in the art upon reading this description.

[0228] For example, compounds exhibiting nonpolar covalent bonds, particularly small molecules such as carbon dioxide, molecular hydrogen, and methane, and compounds that substantially eliminate polar covalent and ionic bonds, are generally characterized by low boiling and melting temperatures and low electrical conductivity. In most compounds exhibiting nonpolar covalent bonds, London dispersion forces control the electronic characteristics of the compound. However, despite being essentially composed of nonpolar covalent bonds, graphene (and similar compounds exhibiting sp2 and / or sp3 bonding and / or substantial coordination between electrons due to the physical arrangement of molecular structures and bonding patterns, as known to those skilled in the art upon reading this disclosure) exhibits significant electrical conductivity. Similarly, compounds exhibiting nonpolar covalent bonds are typically insoluble or only nominally soluble in water (although they are soluble in nonpolar solvents).

[0229] Referring now to FIG. 6, the single integrated microwave plasma torch of FIG. 6 can be configured and operated as shown in Table 2 below, the details of which are described below.

[0230] [Table 2]

[0231] Step S1: Deploy a single integrated microwave plasma torch Figure 6 shows a single integrated microwave plasma torch. The torch has the ability to process solid, liquid, and gaseous reactant species using (for example) small amounts of inert gas or differential pumping vacuum to control gas flow. The torch can be deployed in any environment, including a laboratory, research facility, or large-scale industrial setting.

[0232] Step S2: Operate a single integrated microwave plasma torch for the formation of graphene-filled metal composite ("cobetic") alloys Microwave energy is delivered in a collinear waveguide configuration with a centralized gas supply system for efficient microwave energy absorption. A microwave energy source is used to heat the metal to a semi-molten state. As CH4 (or other hydrocarbon source) decomposes (to its constituent species) in the exhaust plume toward the surface wave plasma gas dissociation tube, carbon radicals can nucleate (e.g., in an organized layer-by-layer manner) on the surface of the metal droplets, energized by the plasma radicals (toward the metal droplets). Microwave thermal plume temperature and plasma energy adjustments enable independent temperature control between melting and plasma decomposition / ionization, which occur within the central region of the pulsed microwave plasma spray torch device 600.

[0233] Process conditions are measured and optimized. The desired process conditions are controlled by or for an integrated microwave plasma torch to directly form graphene-filled metal composites within a single-stage or multi-stage plasma reaction torch. The plasma torch can be modulated within different regions of the surface wave plasma to improve resonance (modulation) time and optimize the formation of targeted metal-carbon structures.

[0234] In addition to the process gas ports shown at the locations shown (such as for the introduction of hydrocarbon process gas 605), additional ports 604 can be provided at different locations. Such additional ports can be used to control how the process gas is introduced into the microwave field and to introduce other process gases. By way of example, the process gas can be SiH4 or NH3. In some implementations, more than one input port for gases or more than one input port for particles (e.g., one for carbon and one for metals) can be included, and the input port locations can be located in different zones of the plasma torch.

[0235] The setup and conditions described above, as well as others, are optimized to result in conditions at the substrate surface that allow the impinging particles to integrate into the film. The as-deposited film is analyzed and characterized according to the methods outlined in step S3 below.

[0236] Step S3: Verification / characterization of graphene (secondary phase) metallic properties Characterization of the as-deposited integrated carbon-metal composite structure can be achieved using several techniques. For example, X-ray photoelectron spectroscopy (XPS) and / or SEM-EDS can be used to determine chemical composition, bond energy (nanoscale carbon detection), and distribution. Energy dispersive X-ray spectroscopy (EDS) and / or SEM, and / or Raman spectroscopy, and / or XRD can be used to determine morphology and / or measure particle size and structural aspects. The electrical and thermal properties, as well as the tensile strength and modulus of the composite can be evaluated using any known technique.

[0237] result The aforementioned technique utilizes a microwave plasma torch to continuously produce metal matrix composites. This process involves the formation of a material nucleation and growth zone within the plasma, followed by an acceleration and impact zone for material integration onto the substrate. Each zone offers unique control over the synthesis / combination and integration of dissimilar materials. That is, the selective and unique combination of alloy particles within the plasma, through control of momentum (primarily kinetics) and thermal energy during impact with the substrate, allows for a unique additive process to control integration parameters such as porosity, defect density, residual stress, chemical and thermal gradients, phase transformations, and anisotropy.

[0238] Various materials are selected for use across a wide range of growth dynamics within the plasma operating environment. In particular, different hydrocarbon gas sources with specific carbon to oxygen and hydrogen ratios, as well as solid metal (or metal alloy) particle sources with different carbon solubilities, melting points, and crystalline structures, can be processed by pulsed energy plasma torch processing systems. Therefore, specific plasma processing parameters can be identified for the nucleation / growth and incorporation of 2D graphene on the metal surface and the simultaneous surface melting of the particles along with the resputtered metal.

[0239] Once graphene is incorporated into metals from a microwave plasma torch, the as-deposited material / film is characterized for "covetic-like" properties. By way of example, these covetic-like properties can be characterized (for example) as follows: (1) chemical composition (e.g., to detect impurities and to detect carbon morphology), (2) carbon distribution (e.g., interstitial (referring to the location of carbon atoms or carbon species within the metal matrix or lattice (i.e., intragranular and intergranular))), (3) electrical conductivity, and (4) mechanical strength of the material. Characterization may include a comparison between the loaded graphene and the unalloyed parent metal. Further, strictly by way of example, as-deposited materials using a microwave plasma torch may exhibit a carbon to metal ratio ranging from about 3% to 90%, inclusive. In some situations, the carbon to metal ratio ranges from about 10% to about 40%, inclusive. In some situations, the carbon to metal ratio ranges from about 40% to about 80%, inclusive. In some situations, the carbon to metal ratio ranges from about 80% to about 90%, inclusive. In some situations, the carbon to metal ratio is greater than 90%, inclusive. The carbon to metal ratio may be influenced (or further influenced) by parameters or specifications that define the coating process (such as temperature, thickness, uniformity, etc.).

[0240] Thus, carbon may be present in amounts unattainable using conventional techniques; for example, the resulting material may contain greater than about 6% carbon by weight, greater than about 15% carbon, greater than about 40% carbon, greater than about 60% carbon, or up to about 90% carbon by weight, according to various embodiments. In various embodiments, carbon may be included in the metal lattice in the aforementioned amounts, such that all or substantially all of the carbon is incorporated into the metal (or other material) lattice, and the grain boundaries / lattice surfaces are substantially or completely free of carbon aggregates and / or agglomerates. Furthermore, carbon is preferably present / located in interstitial sites of the lattice.

[0241] Figure 7 is a diagram 700 illustrating a coating process. The diagram shows a metal substrate subjected to plasma torch spraying of a covetic material, resulting in a composite carbon coating. The metal substrate may include any one or more of aluminum, copper, iron, nickel, titanium, tantalum, tungsten, chromium, molybdenum, cobalt, manganese, niobium, and alloys thereof (e.g., various alloys of Inconel described herein above), or other bulk metal materials. The covetic material may include one or more of carbon, graphene, nano-onions, carbon nanotubes (CNTs), carbide-embedded materials, and the like.

[0242] Plasma torch spraying serves to coat an input material with a deposition material and can be operated using pulsed energy. As indicated, the deposited (e.g., by layer-by-layer sputtering) material can be any one or more of carbon, metal (such as those listed above), and / or oxide or nitride.

[0243] Several advantages emerge from the use of the aforementioned torch. Chief among these is the scalability and versatility of the process for formulating unique, stable metal-carbon composites in a variety of configurations / architectures. These configurations / architectures range from fully dense thin film coatings to thick strips or particles for subsequent remelting and molding / forming into engineered metal alloy components. Each of these species across the aforementioned range exhibits unexpectedly favorable (and desirable) mechanical, thermal, and electrical property enhancements compared to existing parent metal alloy formulations. Furthermore, the tunability of the concentration and distribution of covalently bonded 2D graphene in a metal alloy matrix above the thermodynamic solubility threshold and layer-by-layer formation in a non-equilibrium plasma environment enables a new class of composite materials that can be engineered to address specific applications and / or specific property requirements. Furthermore, this can be done at significantly reduced cost compared to other techniques.

[0244] The improved mechanical, thermal, and electrical properties can be applied to numerous applications using copper and aluminum alloys. By way of example, such applications include, but are not limited to, wire conductors and high-voltage power transmission cables, microelectronic thermal management and heat exchangers, and numerous applications using thin-film electrical conductors, such as batteries, fuel cells, and photovoltaics. In particular, the combination of microwave plasma torch processes and the ability to produce carbon-metal alloys results in significant energy savings in manufacturing, as well as improved thermal efficiency and reduced electrical losses in end-use performance.

[0245] The aforementioned plasma spray technique represents only one type of method for producing covetic materials. Another type involves spraying carbon particles onto small molten metal particles. Such types and various species of such types are shown and discussed in connection with Figures 8A-B, 9, 10, 11, 12, 13, and 14, and the discussion of the figures herein.

[0246] 8A-B are schematic diagrams illustrating a plasma spray process 800 used to spray carbon particles onto small molten particles. Optionally, one or more variations of plasma spray process 800 (or any aspect thereof) may be implemented in terms of the architecture and functionality of the implementations described herein. Plasma spray process 800, or any aspect thereof, may be implemented in any environment.

[0247] The plasma spray technique described is used in a variety of coating processes in which a heated material is sprayed onto a surface. The feedstock (e.g., coating precursor) is heated by electrical means (e.g., plasma or arc) and / or chemical means (e.g., via a combustion flame). Use of such plasma spray techniques can provide coatings having thicknesses ranging from about 20 μm to about 3 mm, depending on the process and feedstock. Coatings can be applied over large areas and at high deposition rates. Using the aforementioned techniques, deposition rates are much higher than can be achieved by conventional coating processes such as electroplating or physical and chemical vapor deposition.

[0248] In addition to (or instead of) the exemplary materials listed above, types of coating materials available for plasma spraying include metals, alloys, ceramics, plastics, and composites. These are fed to the spray torch in powder or wire form, then heated to a molten or semi-molten state and accelerated toward the substrate in the form of micrometer-sized particles. Combustion or electric arc discharge can be used as the energy source for plasma spraying. The resulting coating is created by the accumulation of multiple layers of spray particles. In many applications, the surface of the substrate is not significantly heated, facilitating the coating of many materials, including most combustibles.

[0249] Figure 9 is a scanning electron microscope image 900 showing the effect of spraying carbon particles (e.g., with particle sizes between 20 nm and 40 μm) onto small molten metal particles. Carbon particles sprayed onto small molten metal particles can be used for a variety of specialized applications. For example, plasma aluminum-graphite composites can be specifically designed to provide coatings for turbine engines. Alternatives include the use of aluminum and titanium alloys. The growth rate of this plasma spray coating material is parabolic. Plasma spray coating materials deposit over a short time period, and their deposition is largely temperature independent. To prepare the material surface, certain processes include preheating the material. In some implementations, grit blasting is also performed to prepare the material surface. In some implementations, some of the particles sprayed onto the surface remain hot enough to form a covetic bond with the substrate surface. In other cases, the small molten particles are at a temperature sufficient to form a metal-to-metal bond.

[0250] The use of microwave plasma torch technology disclosed herein allows for improved material production compared to the use of conventional torches. Specifically, the power control limitations and other design constraints inherent in conventional plasma torches limit their ability to independently control the input materials and other conditions necessary to produce carbon effective for producing covetic materials exhibiting sufficiently high quality and uniformity.

[0251] FIG. 10 shows a chart illustrating a graphene growth temperature profile 1000 and a binary phase diagram. Optionally, one or more variations of the graphene growth temperature profile 1000, or any aspect thereof, may be implemented in terms of the architecture and functionality of the implementations described herein. The graphene growth temperature profile 1000, or any aspect thereof, may be implemented in any environment. The figure also shows a binary phase diagram, with the x-axis being the carbon concentration of a selected metal (such as copper as shown) expressed in atomic percent. The temperatures in the temperature profile of the figure are also shown in the phase diagram. Various metals (e.g., silver, tin, etc.) can be used. In some cases, alloys are formed.

[0252] The general idea behind the growth of single-layer graphene (SLG) or few-layer graphene (FLG) on molten metal is to dissolve carbon atoms in a transition metal melt at a specific temperature and then precipitate the dissolved carbon (referring to producing a solid from a solution) at a lower temperature.

[0253] This schematic shows graphene growth from molten nickel by (for example): (1) melting the nickel in contact with graphite (as a carbon source), (2) dissolving carbon in the melt at high temperature, and (3) lowering the temperature for graphene growth.

[0254] As shown, maintaining the melt in contact with a carbon source at a given temperature leads to dissolution and saturation of carbon atoms in the melt due to a binary metal-carbon phase transition. As the temperature is reduced, the solubility of carbon in the molten metal decreases, and excess carbon precipitates at the top of the melt.

[0255] FIG. 11 is a cross-sectional view of a (conventional) plasma flame apparatus 1100. The illustration is provided to distinguish the use of a conventional plasma flame apparatus compared to the use of a microwave plasma torch as disclosed herein. Specifically, while the use of a conventional plasma flame apparatus can produce diamond or diamond-like materials on the surface of a metal, the process requires significant time for material dissolution and diffusion of carbon for the final material to deposit on the surface of the metal. As disclosed herein, during the fabrication of metal-carbon composite materials having implementations disclosed herein, graphene is desirably grown and anchored interstitially between layers (or within lattice or matrix locations) of the metal or metal-containing composite. However, this requires rapid temperature regulation. Unfortunately, conventional plasma torches do not adequately control the temperature and other conditions necessary to reduce the size of interstitial carbon structures to the nanometer scale (which may be desirable in connection with achieving the cobetic materials desired herein).

[0256] In contrast, to provide sufficient detailed control over the temperature and other conditions required to reduce the size of the interstitial carbon structures to the nanometer scale, a pulsed microwave reactor (related to the implementation disclosed herein introduced above) and corresponding process is shown and described in FIG. 12 .

[0257] 12 illustrates a pulsed microwave process flow 1200 used in "growing" graphene, which refers to the systematic layer-by-layer deposition or application of graphene to a substantially flat exposed surface of molten metal particles. Optionally, one or more variations of pulsed microwave process flow 1200, or any aspect thereof, may be implemented in terms of the architecture and functionality of the implementations described herein. Pulsed microwave process flow 1200, or any aspect thereof, may be implemented in any environment.

[0258] When using the illustrated pulsed microwave process flow 1200, graphene is grown on small molten particles. This is achieved by interactions within the pulsed microwave reactor that occur around the inlet 1204 (e.g., where the metal powder and carrier gas are injected into the reactor chamber). In addition to the inlet 1204, process gas port 1202 and additional ports (e.g., additional port 12031 and additional port 12032) are provided at different heights on the side of the reactor apparatus. A waveguide traverses at least the distance from the location of the process gas port 1202 on the side of the reactor to the location of the inlet 1204 on the side of the reactor. Details of how to create and use ports for the introduction and continuous supply of material into such a reactor to grow graphene on small molten particles are disclosed further below. More specifically, certain components of the reactor of FIG. 12 are shown and described with reference to FIG. 13.

[0259] 13 is a perspective view of a conventional pulsed microwave plasma spray waveguide apparatus 1300 used to grow graphene on small molten particles. Optionally, one or more variations of the pulsed microwave plasma spray waveguide apparatus 1300, or any aspect thereof, may be implemented in terms of the architecture and functionality of the implementations described herein. The pulsed microwave plasma spray waveguide apparatus 1300, or any aspect thereof, may be implemented in any environment.

[0260] In this implementation, microwave delivery components and a pulsed power supply are integrated to form a "surfaguide" (or similar) gas reactor. As shown, the combination of these components is configured to facilitate the growth of graphene on small molten particles using a microwave plasma torch.

[0261] An alternative approach is to perform microwelding using a tungsten inert gas (TIG) plasma source to partially or completely melt the metal. Such a microwelding technique is shown and described in connection with FIG. 14.

[0262] 14 is a schematic diagram of a micro-welding technique 1400 used to grow graphene on small molten particles. Optionally, one or more variations of the micro-welding technique 1400, or any aspect thereof, may be implemented in terms of the architecture and functionality of the implementations described herein. The micro-welding technique 1400, or any aspect thereof, may be implemented in any environment.

[0263] A low-power, low-flow TIG welder power supply and control unit can be effectively used with a custom plasma containment section to heat any type of metal particle. As shown, the exhaust plume, when inserted into a surface wave plasma gas dissociation tube, can maintain a temperature high enough to grow graphene. This growth mode, involving control of plasma radicals composed of hydrocarbons and other additive gases formed under non-equilibrium conditions, offers many tuning opportunities that can be utilized with many different configurations of microwave plasma spray equipment. Figures 15, 18A1, 18A2, 18B, 18C, and 18D, as well as other figures and corresponding descriptions, disclose example configurations of plasma spray equipment.

[0264] 15 is a schematic diagram of a plasma spray apparatus in a coaxial configuration 1500. Optionally, one or more variations of the coaxial configuration 1500, or any aspect thereof, may be implemented in terms of the architecture and functionality of the implementations described herein. The coaxial configuration 1500, or any aspect thereof, may be implemented in any environment.

[0265] In a coaxial-style implementation, microwave energy delivery is achieved by feeding TEM waves into an antenna, the outer portion of which is a quartz tube, around which powdered metal particles are flowed. The gas fed into the central region in this example is a hydrocarbon gas, such as methane, which absorbs microwave radiation. The powder is heated by microwave energy emitted from the central region and external induction heating, which melts the metal powder (in particle form) near the inclined portion or tip of the reaction chamber, as shown. When CH4 decomposes (into its constituent species, carbon, hydrogen, and / or their derivatives), carbon radicals nucleate on the surface of the molten metal droplets due to the energy of the plasma radicals. Adjusting the microwave duty cycle, induction heating, and plasma characteristics facilitates maintaining different temperatures between the melt and the plasma decomposition / ionization region. Furthermore, non-equilibrium temperatures enable (and promote) internal lattice alignment of graphene / carbon, and rapid quenching creates conditions that promote further covalent material growth.

[0266] 16 is a schematic diagram of a plasma spray apparatus 1600 illustrating the evolution of a material by processing through a series of non-equilibrium energy conditions. Optionally, one or more variations of the plasma spray apparatus 1600 (or any aspect thereof) may be implemented in terms of the architecture and functionality of the implementations described herein. The plasma spray apparatus 1600, or any aspect thereof, may be implemented in any environment.

[0267] The diagram shows the evolution of the material as it passes through the device. Specifically, the diagram shows a region near the tip where a different evolutionary change occurs, as graphene grows on small particles of molten metal. This material is then deposited on a substrate.

[0268] 17 shows a surface wave plasma system 1700 for growing graphene on molten particles. Optionally, one or more variations of the surface wave plasma system 1700, or any aspect thereof, may be implemented in terms of the architecture and functionality of the implementations described herein. The surface wave plasma system 1700, or any aspect thereof, may be implemented in any environment.

[0269] In the configuration shown, a feed gas is supplied to the central region of the apparatus. In this example, a hydrocarbon gas, such as methane, is used. The hydrocarbon gas absorbs microwave radiation, thereby providing a heat source to heat the metal powder. Thus, the metal powder is heated by both (1) microwave energy emitted from the central region and (2) external induction heating, melting near the tip to a molten state. When the hydrocarbon gas decomposes, carbon radicals nucleate on the surface of the molten metal droplets due to the energy of the plasma radicals.

[0270] FIG. 18A1 illustrates an axial magnetic field configuration 1810 for a plasma spray torch. The formation of covetic material is contemplated using several different apparatus and corresponding processes. Any of the aforementioned apparatus and corresponding processes can be tailored to achieve specific conditions for the formation of covetic material. In the specific axial magnetic field configuration shown, the process involves generating an electric field 1804 between electrodes to cause current flow through a melt of metal and carbon material. Specifically, as shown, a specially configured plasma torch has an externally controlled magnetic field where the molten particles form a plasma, which then becomes a metaelectrode. The electrode on the opposite side of the magnetic field is formed by the growth plate 1803 shown. The covetic material is accelerated through an acceleration zone 1821 and then deposited on a surface. The formed alloy and covetic material continue to deposit on the growth plate and / or on previously deposited material in an impact zone 1823. This deposition technique results in a material with a uniform and high carbon loading.

[0271] Input materials can be selected and varied to achieve materials exhibiting specific properties. For example, as shown, inputs to a plasma spray torch can include various input gases 1812 and input metal and / or carbon particles 1818. These inputs can be introduced into one or more input ports 1862. In some cases, the input metal and / or carbon particles are entrained in the input gas 1812 stream. Additionally, the growth plate can change its size and composition during ongoing deposition. For example, as shown, the growth plate 1803 can initially be a substrate 1816 onto which hot cobetic material is deposited in a torch stream that at least partially melts the substrate as the cobetic material is deposited. The deposited hot cobetic material cools from a molten or partially molten state to form a quench layer.

[0272] Any number of layers can be formed in this manner. The temperature at the substrate and / or at or near the top layer can be controlled so that when the next layer of material lands on the molten metal of the previously deposited layer, the newly deposited layer grows laterally, producing monolayer graphene on the surface of the molten metal. This mechanism distinguishes it from other techniques, at least in that, in contrast to conventional metal melting methods 103 in which carbon precipitates from a molten metal slurry, the application of the plasma spray torch method 104 disclosed herein results in quenching so quickly that the carbon does not have enough time to precipitate from the matrix. Thus, the covetic bonds remain intact throughout the layer. After a few seconds, the quench forms a solid mass of metal and well-dispersed carbon, and then another layer can be sprayed on top, for example, thereby forming a layer of grown, captivated, and rapidly quenched monolayer graphene, producing a truly covetic material with an extremely high carbon loading within the matrix. As an example, when using conventional metal melting method 103 (see FIG. 1A), carbon loadings of 6% carbon metal can be achieved. In contrast, when using plasma spray torch method 104 (see FIG. 1A), carbon loadings of 60% are easily achieved. In some cases, by tightly controlling the inputs and process parameters of the plasma spray torch and its environment, carbon loadings can approach 90% carbon in the resulting material.

[0273] Experimental results using a plasma spray torch indicate that high-load, highly uniform covetic layers can be formed by at least two rapid-quench (e.g., "splat") methods. The first method involves introducing carbon particles to coat metal particles (e.g., within the plasma), and the resulting hot mixture is sprayed onto a much cooler substrate. The second method involves producing graphene within the plasma and then introducing molten metal to coat the graphene. In both cases, true covetic (referring to a combination of covalent and metallic chemistry) bonding occurs during the plasma plume, and the rapid quench in the spray acts to trap the mixture in an organic-metal lattice.

[0274] As shown in FIG. 18A2, the depth or thickness of the quench layer 1824 can be made thicker or thinner by controlling the distance between the plasma flame 1814 and the substrate, and / or by controlling the temperature at the substrate 1816 (e.g., higher or lower than ambient temperature), and / or by controlling the pressure in and around the reactor.

[0275] Figure 18B shows a radial magnetic field configuration 1820 for a plasma spray torch. In this configuration, the molten particles form a plasma within the torch, which becomes the meta-electrode. The other electrode is formed on the side of the inner wall.

[0276] The above-described configurations of Figures 18A1, 18A2, and 18B are merely exemplary. Other configurations with different input materials and different input port configurations are contemplated without departing from the generality of the plasma spray torch disclosed herein. Furthermore, different configurations with different input materials and different input port configurations can achieve the same intended results. For example, two different configurations tailored to achieve the same resulting material are shown and described in connection with Figures 18C and 18D. Specifically, the example configurations of Figures 18C and 18D can be used for plasma spray torch deposition of ceramic film materials on carbon-containing particles (e.g., graphene-containing particles).

[0277] Indeed, thin film deposition of carbon-containing materials (e.g., by atmospheric pressure chemical vapor deposition (APECVD) and / or other variants of chemical vapor deposition (CVD)) has permeated many areas of materials processing. Various composites and coatings incorporating such carbon-containing materials can exhibit improved physical properties (e.g., strength, resistance to corrosion, etc.). The morphological characteristics of various 2D and 3D carbons result in these improved physical properties of the composites and coatings due to the molecular-level organization within the carbon-containing materials. In some cases, the use of 2D and 3D carbon in composites and coatings significantly increases the resulting carbon-containing materials' resistance to high temperatures; however, in some cases, these high temperatures rise above approximately 2100°C, which is high enough to combust the 2D and 3D carbon itself. Unfortunately, destroying the 2D and 3D carbon eliminates the benefits inherently provided by the carbon in the composite or coating. Therefore, deposition techniques (e.g., plasma spray torch configurations) are needed to create composites or coatings that can withstand temperatures even higher than the combustion temperature of carbon.

[0278] Figure 18C illustrates such a configuration, strictly by way of non-limiting example. By adjusting the inputs and various reactor conditions, graphene-containing materials can be coated with a heat-absorbing layer of organically modified silicon (ORMOSIL). Deposition of ORMOSIL ceramic material onto graphene-containing materials can be achieved by several methods, including via a process of atmospheric reactive plasma-enhanced chemical vapor deposition using a silicon-containing precursor 1841 (such as hexamethyldisiloxane) and a reactive gas (such as oxygen). This particular mixture of silicon-containing precursor and oxygen becomes reactive in the plasma. Molecular dissociation occurring within the plasma flame results in the deposition of silicon oxide on surfaces such as the aforementioned growth plate 1803. To achieve this, reactor conditions are controlled so that organically modified silicon ceramic is deposited on the surfaces of carbon-containing particles as they form within the reactor. Controlling reactor growth and deposition (e.g., by controlling the APECVD process) results in a thin quartz coating around the carbon-containing particles, which is then deposited on the substrate. The thin quartz coating acts as a flame retardant layer to prevent the carbon-containing particles from burning at high temperatures.

[0279] Figure 18D shows an alternative configuration, strictly by way of non-limiting example. As shown, metal and / or carbon-containing material is loaded into a reactor. Microwave energy 1822 is controlled to achieve at least a temperature that dissociates the carbon-containing material (e.g., T(c-dis) in Figure 10). Silicon-containing precursor 1841 (e.g., HMDSO, HMDSN) is introduced into the plasma flame, and the temperature in the plasma afterglow is reduced. As the temperature decreases, carbon particles begin to form and become coated with silicon oxide. The silicon oxide-coated carbon particles are then deposited on a substrate.

[0280] In one implementation, a thin layer, perhaps 10 nm thick, of these 3D materials can be deposited on a substrate and will not burn or catch fire even at 1200°C. This is because pure carbon (such as graphene) is crystallized; it is not an amorphous material, for example. Rather, it is simply reduced to a state where it will not burn further.

[0281] In one use case, the plasma spray torch technology mentioned above can be used to create new types of non-eutectic solders, or in another use case, the plasma spray torch can spray a coating of material directly onto a substrate to protect the underlying material from oxidation.

[0282] In addition to creating a material that will not burn at 1200°C at atmospheric pressure, placing quartz around the material often provides significant advantages in applications.

[0283] In addition to organically modified silicon, other organic materials can be used to coat carbon particles or layers. The characteristics of the coating can be controlled. For example, the pores on the surface of the thermally sprayed material can be adjusted to be hydraulically smooth.

[0284] A plasma spray torch can be used to form a heat-absorbing, glass-coated, non-flammable graphene composed of graphene and silicon, where the silicon coats the graphene, allowing the graphene to withstand temperatures above 1600°C. Such heat-absorbing, glass-coated, non-flammable graphene absorbs infrared energy.

[0285] One specific method for producing an organically modified silicon coating includes (for example): (1) introducing a silicon-containing precursor into a plasma spray torch apparatus; (2) combining the silicon-containing precursor with a carrier gas having carbon particles entrained in the precursor gas; and (3) coating the carbon particles with silicon.

[0286] The characteristics of the flame retardant and infrared shielding material resulting from the plasma spray torch configurations of Figures 18C and / or 18D can be tailored, at least in part, by controlling the time-temperature path through the reactor. More generally, the characteristics of the material resulting from the plasma spray torch configurations of Figures 18A1, 18A2, 18B, 18C, or 18D can be tailored, at least in part, by controlling (e.g., pulsing) the microwave energy in the reactor.

[0287] FIG. 19 is a chart 1900 showing energy versus time during pulse-on and pulse-off. More specifically, this chart shows one complete time cycle from time T=0 to 50 microseconds during which the microwave is continuously on, with the remainder of the cycle shown showing the microwave off. The plotted curves show (1) the change in density and (2) the change in temperature over the cycle. At time T=0, the temperature is at a minimum point (such as that shown at the origin of the chart). The temperature rises rapidly, then drops, while the plasma density reaches a relatively stable value. When the microwave is turned off at time T=50 microseconds, both the plasma density and the temporal electron temperature drop rapidly. The pulse time and duty cycle can be controlled to achieve a specific density and temperature at any given time.

[0288] FIG. 20A1 is an image showing the organometallic bonding that occurs when combining carbon and copper using a plasma spray torch. As shown, carbon 2052 is deeply embedded within copper 2054. As generally understood and referred to herein, organometallic chemistry refers to the study of organometallic compounds, i.e., chemical compounds containing at least one chemical bond between a carbon atom of an organic molecule and a metal, including alkali metals, alkaline earth metals, and transition metals, and in some cases extended to include metalloids such as boron, silicon, and tin. In addition to bonding to organic (organyl) fragments or molecules, those bonded to "inorganic" carbon, such as carbon monoxide (metal carbonyls), cyanides, or carbides, are also generally considered organometallic. Related compounds, such as transition metal hydrides and metal phosphine complexes, while not necessarily strictly organometallic, may be included in the discussion of organometallic compounds.

[0289] In organometallic chemistry, organocopper compounds contain a carbon-copper chemical bond and may have unique physical properties, synthesis, and reactions. Organocopper compounds can be diverse in structure and reactivity, but are still somewhat limited in oxidation state to copper(I), such as Cu+ shown here. As a d10 metal center, it is related to Ni(0), but due to its higher oxidation state, it participates in fewer pi backbonds. Organic derivatives of Cu(II) and Cu(III) can be envisioned as intermediates, but are rarely isolated or even observed. From a geometric perspective, copper(I) adopts a symmetric structure, consistent with its spherical electron shell. Typically, it can adopt one of three coordination geometries: linear dicoordinate, trigonal planar tricoordinate, and tetrahedral tetracoordinate. Organocopper compounds form complexes with a variety of soft ligands, such as alkylphosphines (R3P), thioethers (R2S), and cyanides (CN-).

[0290] By any one or more of the aforementioned techniques, the carbon shown in Figures 20A1 and 20A2 is chemically bonded to the copper, as opposed to being adjacent to and attached to it simply by van der Waals forces (e.g., referring to distance-dependent interactions between atoms or molecules). Unlike ionic or covalent bonds, van der Waals forces do not arise from chemical electronic bonds and are relatively weak and therefore susceptible to disturbances. Furthermore, van der Waals forces rapidly dissipate at longer distances between the interacting molecules. Instead, what is desired is an organometallic bond between the metal and the carbon.

[0291] FIG. 20A2 is an image showing a graded composition applied to a substrate material, depicting three material property zones. Bulk metal zone 2066 is the first of the three material property zones. As shown, the first material property zone includes a metal in a first crystallographic structure, with substantially metallic bonds between metal atoms present in the first material property zone. This first material property zone is substantially adjacent to a second material property zone that at least partially overlaps the first material property zone. Covetic material zone 2064 includes at least some carbon atoms in a second crystallographic structure, with at least some non-polar covalent bonds between some of the carbon atoms present in the second material property zone and metal atoms present in the first material property zone. Top surface zone 2062 is a third material property zone that at least partially overlaps the second material property zone. This top surface zone further includes carbon atoms oriented in a third crystallographic structure. The third crystallographic structure is characterized by at least some non-polar covalent bonds between individual carbon atoms of the additional carbon atoms present in the third material characteristic zone. In various implementations, some metal atoms may be present in any of the zones and some carbon atoms may be present in any of the zones. However, this implementation is characterized by a high metal content zone 2074 adjacent to the bulk metal zone 2066. In various implementations, some carbon atoms may be present in any of the zones and some metal atoms may be present in any of the zones. However, this implementation is characterized by a high carbon content zone 2072 adjacent to the top surface zone 2062.

[0292] FIG. 20B is a material evolution chart 20B00 illustrating several layering configurations that occur when adding carbon to bulk aluminum. In these implementations, the material is sprayed onto an existing carbon-rich covetic substrate or carbide layer, and carbon-carbon bonds are created by carbon sintering and / or metal melt encapsulation, thereby creating adhesion to form a composite film. Material evolution chart 20B00 is just one example of a combination material (silicon carbide) being sprayed onto an aluminum bulk material. The process may be tailored to create a covetic or covetic-like film deposited on the bulk material. The resulting material can then be coated to create a functionalized top layer. One possible configuration of an apparatus for spraying a combination material onto a substrate is shown in FIG. 21A.

[0293] FIG. 21A illustrates an apparatus for thermally spraying a molten mixture of materials onto a substrate. The diagram shows a microwave reactor including multiple regions within a containment vessel. Pulsed microwave energy is delivered into the containment vessel. A hydrocarbon process gas 605 is provided through an inlet port. The microwave energy heats the process gas to a temperature high enough to form a plasma. The expansion of the material within the containment vessel creates a plasma plume. The continuous addition of material into the containment vessel, combined with this expansion, creates a torch effect within and around the plume. Due to the high temperatures within and around the plasma plume, carbon dissociates from hydrogen, thereby forming several different hydrocarbon species (CH3, CH2, etc.). As the temperature continues to increase (e.g., in the first region 2104 as shown), all or nearly all of the carbon atoms dissociate from the hydrogen. The hydrogen-only species are separated from the solid carbon species using any known technique (e.g., using a gas-solid separator).

[0294] At the interface between the containment vessel first region 2104 and the containment vessel second region 2106, molten metal or molten metal composite, or molten ceramic-metal, or metal matrix, or any type of metal mixture is introduced into the containment vessel via a second inlet (as shown). The location of the second inlet is selected based on the size of the plasma plume and / or the temperature of the molten metal at the point of entry into the containment vessel. More specifically, the metal melt 2108 is introduced into the reactor at a location where the molten metal mixes with the carbon species. As the mixture flows (e.g., at high velocity) through the containment vessel, the mixture cools to a lower temperature. The flowing mixture exits the containment vessel at high velocity such that the carbon and molten metal mixture is sprayed from the exit port 2110. The mixture is deposited onto a target substrate 2116 (e.g., via thermal spraying of a thermal spray material 2112). Various mechanisms for controlling the uniformity of the thermally sprayed material 2112 and / or the resulting deposited material 2114 are shown and discussed in connection with Figures 23A-23D.

[0295] The temperature in the second region is low enough that at least a portion of the carbon precipitates from the mixture. However, most of the dissociated carbon remains mixed with the molten metal. When the molten metal mixed with carbon reaches the target substrate 2116, it cools and solidifies. During the transition from the molten mixture to the solid deposit, the carbon becomes trapped between the metal and carbon layers. At a certain temperature, the carbon forms nonpolar covalent bonds with the metal, resulting in a covetic material. This covetic material exhibits various mechanical, thermal, electrical, and tribological properties due to the increased cohesion (e.g., nonpolar covalent bonds) between the metal matrix and the carbon.

[0296] Such covetic materials result from the use of pulsed microwave energy to control the energy distribution of the constituent materials within the first and second reactor regions. More specifically, the energy distribution of the constituent materials within the first and second reactor regions can be controlled in part by pulsing the microwaves and in part by pre-melting the metal particles in an environment external to the reactor chamber (e.g., to introduce fully molten or partially molten metal into the reactor chamber). Any known techniques can be used, alone or in combination, to melt the metal particles. Thus, the degree and / or mixture of fully or partially molten particles can be controlled.

[0297] FIG. 21B illustrates a method for thermally spraying a cobetic material onto a substrate. This method can be used in conjunction with the apparatus of FIG. 21A. As shown, this method is carried out using a microwave reactor having a process gas inlet, a metal melt inlet, and an outlet port. Prior to operation, the microwave reactor is configured with a hydrocarbon process gas inlet, a metal melt inlet, and an outlet port (operation 21B02). In operation 21B10, the inlet functions to introduce the hydrocarbon process gas into a first region of the reactor. The use of microwave energy increases the temperature in the first region of the reactor, causing the hydrocarbon process gas to dissociate into carbon and hydrogen species before reaching the metal melt. A different inlet functions to introduce the metal melt into a second region of the reactor (operation 21B20). The increased temperature in the second region is maintained until the dissociated carbon mixes with the metal melt (operation 21B30). The plume effect acts to move the mixture into a third region of the reactor (operation 21B40). Movement away from the microwave energy source has the effect of lowering the temperature of the mixture until at least a portion of the carbon condenses from the mixture (operation 21B50). However, even as the temperature drops, the plasma torch effect acts to move the mixture through an exit port at high velocity (operation 21B60). Thus, the molten mixture is sprayed onto a substrate (operation 21B70).

[0298] FIG. 21C is a schematic diagram illustrating the plasma spray process used to thermally spray the film. As shown, carbon radicals, polycyclic aromatic compounds, graphene sheets, and metal particles are mixed at high temperatures within a plasma reactor (e.g., indicated by the first region 2104). Nucleation occurs at these high temperatures, and growth and aggregation begin as the temperature inside the reactor decreases (e.g., indicated by the second region 2106). One possible growth mechanism is illustrated by the coating of submicrometer-sized aluminum particles with few-layer graphene. These submicrometer-sized aluminum particles are bonded by a combination of metallic, nonpolar covalent, and covalent bonds. More specifically, as shown on the 2 nm scale, carbon atoms bond to aluminum atoms. The carbon atoms are organized into coherent graphene planes arranged in an aluminum matrix, preferably interdigitated between the basal planes of the aluminum matrix. The foregoing discussion of aluminum is merely exemplary. Other metals may also be used. In fact, coherent graphene planes can be arranged not only in a face-centered cubic (FCC) metal lattice, but also in a body-centered cubic (BCC) metal lattice, or even in a hexagonal close-packed (HCC) metal lattice (again, preferably between the basal planes).

[0299] The coated particles are then sintered to form particles having a diameter of about 100 μm. These semi-molten particles are then accelerated through a reactor and impinge on a substrate (e.g., a first pass) or on a previously deposited layer of impinging particles (e.g., a second or Nth pass).

[0300] Figure 22A shows an apparatus for coating carbon particles with molten metal. The configuration of the apparatus in Figure 22A differs from that of Figure 21A at least in that the introduction of molten metal is controlled using melter 2209. The metal melt is controlled to produce molten metal that coats the carbon particles as the molten metal is introduced into the reactor.

[0301] FIG. 22B illustrates a method for coating carbon particles with molten metal. Prior to operation, a microwave reactor is configured with a hydrocarbon process gas inlet, a metal melt inlet, and an outlet port (operation 22B02). In operation 22B10, the inlet functions to introduce the hydrocarbon process gas into a first region of the reactor. This method differs from the method of FIG. 21B at least in that, in operation 22B30, temperatures in different regions of the reactor are maintained to form several carbon particle species from the dissociated carbon. The effect of the aforementioned plume functions to move the mixture into a third region of the reactor (operation 22B40). In operation 22B50, at least a portion of the carbon particles are coated with molten metal. Several bonds are formed between the constituent atoms of the carbon particles and atoms of the metal melt. In operation 22B60, the metal-coated carbon particles are moved through the outlet port, thereby further reducing the temperature. When metal coated particles are deposited onto a substrate (operation 21B70), additional bonds are formed between the metal coated carbon and the metal of the substrate.

[0302] 23A, 23B, 23C, and 23D illustrate exemplary deposition techniques, according to some implementations.

[0303] As shown in FIG. 23A, the deposited material has a curved shape characterized by a middle region of higher height and end regions of lower height. In some cases, this is the desired shape of the spot of deposited material. In other cases, it is desirable to spray the deposited material over a larger area. This can be achieved by moving the substrate relative to the spray or by moving the spray relative to the substrate. FIG. 23B shows a flexible substrate 2310 positioned on a supply reel. The flexible substrate may be retracted onto and around a take-up reel. Thus, in the configuration of FIG. 23B, the spray uniformly deposits covetic material on the moving substrate. By controlling the relative motion of the sprayed material 2112 and the substrate, the resulting deposited material has a uniform thickness.

[0304] In some situations, it is desirable to have a non-planar, uniform pattern on the surface of the deposited material. In such situations, the movement of the substrate can be stepped through a series of discrete positions, thus resulting in the pattern of FIG. 23C. Additionally or alternatively, a slotted antenna can be positioned between the thermal spray material 2112 and the substrate. The slotted antenna functions by evenly distributing the thermal spray over the lateral distance of the slotted antenna. Using such a slotted antenna, a single spot of thermal spray material 2112 can have a thickness and surface uniformity substantially as shown in FIG. 23D.

[0305] 24A and 24B illustrate conventional techniques for depositing materials onto a substrate. As shown in FIG. 24A, carbon aggregates are held together by the use of a binder (such as a polymer). This results in a weak bond at the interface between the carbon aggregate and the substrate. FIG. 24B illustrates coating a carbon material onto a substrate using a binder. Conventional deposition using a binder suffers from delamination issues. Furthermore, even when the surface of the substrate is mechanically pretreated and / or pretreated by the deposition of a binder material, the interaction between the substrate and the carbon aggregate is weak.

[0306] As previously discussed, coatings based on depositing materials onto a substrate using binders and / or using coating techniques (e.g., as shown and described in connection with Figures 24A and 24B) suffer from problems of delamination, low strength properties, and other undesirable mechanical properties. An improvement based on plasma spray technology is shown and discussed in Figures 25A and 25B.

[0307] 25A and 25B illustrate exemplary deposition techniques that result in nonpolar covalent bonds at the surface of a substrate, according to some implementations. Specifically, as shown, when the techniques disclosed herein are used, a covetic material is formed through nonpolar covalent bonds between carbon and the substrate. Therefore, no binder is required or used. Furthermore, many of the nonpolar bonds formed at the interface between the substrate and the covetic material are strong covalent bonds. In one particular case, when the substrate is aluminum, nonpolar covalent bonds are formed between the face-centered cubic atoms of aluminum and the hexagonal atoms of carbon. A schematic diagram of the interface bonding is shown in FIG. 25B.

[0308] Figures 26A, 26B, 26C, and 26D show schematic diagrams illustrating how non-polar covalent bonds are formed between square-shaped sites in the face-centered cubic structure of aluminum and hexagonal-shaped sites that occur in certain crystallographic structures of carbon.

[0309] Figure 26A is an orthogonal view showing the square shapes of aluminum's face-centered cubic structure, and Figure 26B is an orthogonal view showing the hexagonal shapes that occur in certain crystallographic structures of aluminum.

[0310] Figure 26C shows one possible superposition of the hexagonal shape that occurs in certain crystallographic structures of carbon on the square shape of the face-centered cubic structure of aluminum. Figure 26D shows nonpolar covalent bonds formed at specific locations. The example of the face-centered cubic structure of aluminum is merely one example. Other metals with other crystallographic structures are also contemplated. It is hypothesized that the unexpected properties exhibited by some embodiments result from the nonpolar covalent bonds between the carbon and metal atoms being sufficient / effective to "capture" all or substantially all (e.g., at least 90%, at least 95%, at least 98%, at least 99%, etc.) of the "free" electrons typically present in compounds exhibiting metallic bonding, thereby altering the properties typically associated with the presence of "free" electrons in metals and metal-containing compounds. For example, certain implementations may feature surfaces of the compositions of the present invention that are substantially free of "free" electrons and therefore exhibit reduced thermal and / or electrical conductivity. Furthermore, in implementations that are substantially free of "free" electrons, the surfaces of the compositions of the present invention do not oxidize when exposed to ambient air.

[0311] Figure 26E shows an example of a layered cobetic material 26E00 in which a graphene-like structure is sandwiched between layers of metallic material. The bottom layer of metallic material is a layer of substrate. The top layer of metallic material is formed from quenched material previously melted in the reactor. The graphene-like structure sandwiched between the layers of metallic material is trapped between two layers of metal due to the formation of intermetallic bonds between the two metal layers. In addition to metallic bonds, other bonds are formed, serving to encase the graphene-like material between the metal layers. In some locations, there are defects in the carbon lattice. Various types of bonds are formed between or near such defects.

[0312] Any or all of the aforementioned techniques for forming covetic materials can be used in many applications involving many different types of substrates. Furthermore, the relative motion between the spray material and the substrate can be controlled to produce a deposition of any desired thickness. Any known technique can be used to control the relative motion. For example, the outlet port can be moved relative to a stationary substrate. This can be accomplished using a handheld or robotically controlled device that moves relative to the stationary substrate. In some cases, a bias voltage can be applied to the substrate so that at least a portion of the material sprayed from the outlet port is electrostatically attracted to the surface of the substrate. This is applicable in applications where the substrate is not uniformly flat. By way of example, applications where the substrate is not uniformly flat can include (1) molded components used in machines exposed to corrosively harsh conditions, (2) turbine blades, (3) heat exchanger components, and the like. Many of these applications are discussed further below.

[0313] In other situations, deposition characteristics (e.g., thickness, lateral uniformity) can be improved through the use and / or combination of various chemical vapor deposition techniques. As just one example, aspects or parameters of plasma-enhanced chemical vapor deposition techniques known in the art can be controlled to optimize the characteristics of the deposited layer of covertic material. As another example, rather than depositing a covertic material onto a surface to form a film or coating, the covertic material can be formed into particles (e.g., by thermal spraying into a cooler environment) and the particles can be collected as a powder. Various techniques for the production and use of powder covertic materials are briefly discussed below.

[0314] Powdered Covettic Material In some situations, rather than forming the covetic material as a film or coating on or within a substrate, the covetic material can be delivered as a covetic material powder. Such powdered covetic material can be collected upon discharge from a reactor, cooled to a temperature below the melting point of the covetic material, and collected as a powder. The powder can then be processed (e.g., stored and transported, poured, mixed) at room temperature. The powder can then be remelted and compressed into a form or remelted and resprayed. By way of example, such powdered covetic material can be formed into components for use in highly corrosive environments using injection molding or extrusion. Many devices can be used, alone or in combination, to form and transport the covetic material powder. Exemplary devices are shown and described in connection with Figures 27A, 27B1, and 27B2.

[0315] FIG. 27A shows an exemplary apparatus 27A00 for producing a powder covetic material 2710 using a cooling zone 2702 that cools the thermal spray material 2112 as it is extruded through the microwave reactor exit port 2110. Any one or more cooling techniques, in any combination, can be used to reduce the temperature of the covetic material in the cooling zone 2702 to a temperature below the melting point of the covetic material. The cooling zone 2702 may host one or more devices for effecting cooling. For example, as shown, the collection vessel 2704 may include one or more devices for creating a cyclone effect within the collection vessel, thereby increasing the time for which the temperature of the covetic material is reduced. In some cases, the time for which the covetic material is cooled is controlled (e.g., by increasing or decreasing the time) so that the covetic material can be annealed with highly ordered bonds. In some cases, controlling the time for which the covetic material is cooled allows the covetic material to crystallize into a highly ordered crystalline structure while still maintaining a powder form. In some implementations, a mechanical tumbler agitator can be installed between the microwave reactor outlet port 2110 and the collection vessel 2704. The tumbler agitator can be cleaned or replaced periodically.

[0316] Alternatively, or in addition, a fluidized bed apparatus can be used in situations where it is convenient and / or necessary to contain and / or transport the powdered covetic material in a fluid. For example, the powdered covetic material can be held (e.g., suspended) in a liquid to avoid the formation of agglomerates and / or agglomerates of the powder particles. In some implementations, a fluidized bed apparatus can be attached between the microwave reactor outlet port 2110 and the collection vessel 2704. One implementation of such a fluidized bed apparatus is shown and described in connection with FIGS. 27B1 and 27B2.

[0317] 27B1 and 27B2 show an exemplary fluidized bed apparatus 27B00 for cooling and processing powdered covetic material within a fluid.

[0318] As shown, a mixture of molten metal and carbon is forced into the top of the fluidized bed 2750 through the reactor's exit port. As the mixture of molten metal and carbon is forced out of the exit port, it cools, forming particles. The particles are subjected to the downward force of gravity (e.g., downward as shown), while process fluid 2754 is forced in from the bottom of the fluidized bed, creating an upward force. Thus, the particles accelerate toward the bottom of the fluidized bed at a slower acceleration rate than that of local gravity. The fluidized bed geometry can partially control the flow dynamics. For example, as shown, the length of the fluidized bed can form a tapered body 2762, where a first end of the tapered body has a first dimension D1 and a second end of the tapered body has a second dimension D2 (where D1 > D2). The temperature within various portions of the fluidized bed can be controlled in part by a power supply 2752 that supplies power to coils (as shown) and / or by a heat source 2760 that heats the process fluid 2754 before it enters the bottom of the fluidized bed.

[0319] The pressures and flow rates and other conditions within the fluidized bed and at the bed's environmental interface act to cause the powder-fluid mixture to collectively behave as a fluid, exhibiting many of the properties and characteristics of a fluid, such as the ability to flow freely under gravity and / or be pumped using fluid handling techniques.

[0320] 27B1 and 27B2, the fluidized bed has multiple ports located at different heights of the tapered body so that a first powder 27561 in the fluid exits at a specific temperature / pressure and a second powder 27562 in the fluid exits at a second, different specific temperature / pressure. The flow through the multiple ports can be controlled so that the collection vessel can accept any ratio or amount of first powder 27561 in the fluid and second powder 27562 in the fluid.

[0321] Method for forming a Covettic material Table 3 shows some non-limiting examples of methods for forming powdered covettic materials.

[0322] [Table 3]

[0323] Exemplary Method 1 In some implementations of Method 1, structured carbon (e.g., a carbon allotrope) is formed in a first region of a microwave reactor (e.g., by dissociation of a hydrocarbon process gas). In a second region, which is cooler than the first region, the structured carbon is modified with a metal to form a metallized carbon material (e.g., an organometallic material). The metallized carbon material is further cooled to a temperature below the melting point of the metal. In some implementations, the metallized carbon material is initially in the form of metal-modified carbon particles. The particles are further cooled to form a powder. The powder can be collected and transported to an application facility. The powder containing the metallized carbon material with covetic bonds can be remelted and used in conjunction with any known technique for forming components from powders. Specifically, by way of example, components can be formed from the powder using die pressing followed by remelting, isostatic pressing followed by remelting, hot forging, metal injection molding, laser sintering, etc.

[0324] Exemplary Method 2 In this method, one or more hydrocarbon gases (or gases and liquids, as the case may be) are introduced into the system. Specifically, by way of example, gases and / or liquids that can be introduced into the system include methane, ethane, methylacetylene-propadiene propane (MAPP), and hexane. In a first region 2104 at a first temperature, carbon atoms are dissociated from other atoms (e.g., dissociated from hydrogen). Molten metal 2108 is introduced into the reactor as metal particles. Next, in a second region 2106, the carbon produced in the first region combines with the metal particles. Carbon may grow on the surface of the metal particles and / or within the metal particles. In some situations and under some conditions, carbon growth includes 2D carbon growth on or within the metal particles. In other situations and / or under other conditions, carbon growth includes 3D carbon growth on or within the metal particles. In any of the above growth situations, growth may occur to the maximum extent permitted by the lattice. For example, the molten metal can be aluminum having a face-centered cubic (FCC) crystal structure, and carbon can form a solid solution with the aluminum up to a certain concentration. In some implementations, carbon forms a solution with the metal up to a concentration determined by the metal properties (such as crystal structure) and then precipitates from the metal-carbon solution to form 2D or 3D carbon on and / or within the metal particles.

[0325] Growth in Method 2 is performed under non-equilibrium thermal conditions. Specifically, various different thermal conditions are controlled (for example): (1) a first temperature (e.g., a higher temperature) in the first zone necessary to control the aforementioned dissociation, and (2) a second temperature (e.g., a lower temperature) in the second zone to control the insipient melting of the metal powder and / or the formation and properties of the metal-carbon particles in the second zone. The temperatures of these two zones can be controlled independently. Using this method, the thermally sprayed material is a true cobetic material that exhibits true cobetic behavior.

[0326] Exemplary Method 3 In a further non-limiting example, the material and / or coating on the input particles can be made or deposited from a mixture of materials such as trimethylamine (TMA), trimethylglycine (TMG), methylacetylene-propadiene propane, etc. The particles can be cooled and collected as a powder. Some examples of particles that can be made from the target material in the first zone are phased carbon, silicon carbide, metal oxides, metal nitrides, or metals. In some cases, the input particles are metals and a compound film (such as a metal oxide or metal nitride) is coated on the metal input particles, while in other cases, the input particles contain a compound material and a metal coating is deposited on the input particles. Some examples of particles that can be made from the input gas in the first zone are carbon allotropes (such as natural carbon), silicon, ZnO, AlOx, and NiO.

[0327] In some implementations, a non-hydrocarbon gas or a gas containing an alcohol is input into a first zone, the first zone including a sputtering device and a power supply, the sputtering device configured to generate multiple ion species from a selected target material. The target material and the ion species combine to form multiple particles. The power supply can be an AC, DC, RF, or high-power impulse magnetron sputtering (HIPIMS) power supply, and can be configured to generate multiple ion species from the target material by adjusting the power, voltage, frequency, repetition rate, and / or other characteristics of the power supply.

[0328] FIG. 27C is a schematic diagram showing the plasma spray process used to produce the powdered Covetic material.

[0329] Powder material processing order A visual representation of an exemplary powder material processing sequence ranging from hydrocarbon cracking and particle nucleation (such as the first region 2104 shown), to graphene growth (such as the second region 2106 shown), to cooling of the semi-molten particles (such as the cooling region shown), and collection of the powder cobblestone material (e.g., in a collection region and in a collection vessel 2704) is shown in Figure 27C. The mechanisms underlying the effectiveness of the exemplary powder material processing sequence will now be briefly discussed.

[0330] In the absence of metal precursors (whether in metal-organic or particle form), microwave plasma dissociates methane to form carbon radicals (and polyaromatic compounds / acetylenes), which then form few-layer (FL) graphene (or stacked lamellae) structures, respectively. However, in the presence of metal precursors in the plasma zone (see, e.g., the reactors in Figures 21A and 22A), the metal (either from organometallic nuclei or particles) can serve as seed sites for heterogeneous carbon growth (e.g., carbon in the form of ionized radicals, graphene nuclei, or polyaromatic compounds (acetylenes)).

[0331] When using metals with low solubility, such as Al or Cu, graphene sheets can grow on the metal surface (e.g., via adatoms / monomers or as clusters). The characteristics of growth depend, at least in part, on the symmetry and minimization of interfacial free energy at the metal surface. Thus, carbon growth occurs on the metal particles along with resputtering events of metal atoms at the surface, producing mixed and / or layered metal / carbon structures. As is known in the art, the radius (e.g., surface curvature) of the metal particles can affect the solubility of carbon in the metal particles. As an example, a smaller radius (e.g., corresponding to a higher curvature) increases the solubility above equilibrium (on a flat surface), and this increased solubility can, in turn, affect the thickness of the graphene layer.

[0332] Once the powdered Covettic material 2710 is collected in the collection vessel, the powdered Covettic material may be further processed using conventional techniques (such as injection molding techniques, other techniques using powdered metals, etc.).

[0333] Manufacturing technology using powdered Covettic materials 28 illustrates a method for manufacturing a component from a powdered covetic material using injection molding techniques. As shown, the method begins with collecting a set of properties for a component to be used in a particular application and / or environment (operation 2810) and then selecting a particular powdered covetic material based on at least one of the properties for the application or environment (operation 2820). The selection may be based on desired mechanical properties of the component, and / or may be based on the desired corrosion resistance of the component in an environment corresponding to its intended application, and / or other desired properties. The selection may be based on multiple desired properties, and in some cases, a selection tool solved an optimization problem based on the set of properties and an objective function.

[0334] Once a covertic material is selected (operation 2820), the selected powder covertic material 2825 is melted (operation 2830) and introduced into a mold (operation 2840). A predetermined temperature and a predetermined pressure are maintained within the mold for a predetermined time (operation 2850), after which time the temperature and pressure within the mold are brought to approximately 30°C and atmospheric pressure (operation 2860). The component is removed from the mold (operation 2870) and deployed for its intended use (operation 2880).

[0335] As discussed above, the selection of a particular covetic material may be based on multiple desired properties, some of which may be used as variables in an objective function. In some cases, the selection of a particular covetic material may be based on a particular key property (e.g., mechanical strength, weight, corrosion resistance, etc.). In some cases, the property of interest is the ratio of another property, e.g., strength to weight, specific heat to weight, etc. In some cases, the key property should be maximized (or minimized) subject to one or more constraints on other properties.

[0336] As such, powdered Covettic materials can be deployed in a wide range of applications. In many cases, components made from powdered Covettic materials outperform components made from other materials. Some exemplary applications correlating with certain key properties are shown and discussed in connection with Figure 29 below.

[0337] Figure 29 is a diagram 2900 illustrating various properties of Covetic materials. The properties illustrated include mechanical properties, thermal conductivity, resistance to oxidation, durability, resistance to softening at high temperatures, resistance to fatigue, and electrical conductivity. Individual and / or combinations of these parameters are key when selecting a particular Covetic material for a particular application.

[0338] Specifically, as one example, resistance to oxidation may be a key parameter in selecting a Covetic material for use in manufacturing corrosion-resistant valves. As another example, when selecting a particular Covetic material for use in manufacturing blades for aircraft engine turbines, mechanical attributes such as strength-to-weight ratio, subject to minimum strength constraints, may be key mechanical attributes. The blades may also need to exhibit very high fatigue resistance.

[0339] Typically, Covetic materials not only exhibit the aforementioned properties but also have a lower density than the metals or alloys used in producing the Covetic powder. The lower density often results in a correspondingly lower weight of the formed component compared to the same component made from a metal or alloy without the carbon load. Thus, truck parts (such as the cab component shown), automobile parts (such as doors, fenders, and roof panels), motorcycle parts, bicycle parts, and various components (such as structural members) for aircraft, watercraft, and / or spacecraft or platforms can take advantage of the lower strength-to-weight ratio of Covetic materials compared to the base metals or alloys used to produce them.

[0340] As another example, Covettic materials often exhibit excellent thermal conductivity, such that structural members formed from Covettic materials may be used in high temperature applications (e.g., heat sinks in electronic devices, industrial heat exchangers, etc.).

[0341] As yet another example, Covetique materials often exhibit exceptional corrosion resistance. More specifically, Covetique laminates made using the techniques described above exhibit very high corrosion resistance, even at the top layer (e.g., at the component-environment interface). This property is particularly noteworthy when components made with Covetique materials are exposed to harsh environments.

[0342] As yet a further example, Covetic materials can be tailored for surface smoothness. More specifically, Covetic laminates produced using the aforementioned techniques exhibit extremely high surface smoothness. This surface smoothness characteristic is particularly noteworthy when the Covetic material functions as a heat shield (e.g., required in applications where surface friction (such as that generated when a fluid passes over a surface at high speed) generates unwanted heat on the surface). By using the techniques disclosed herein, specific compositions of Covetic materials and / or specific techniques disclosed herein for depositing Covetic materials can result in hydrodynamically smooth surfaces that can, in turn, be used in aircraft and / or spacecraft.

[0343] In certain implementations, one set of properties may be prioritized over other properties. For example, the surface of a spacecraft (such as a satellite) may be required to be substantially non-reflective to a range of electromagnetic radiation (e.g., substantially non-reflective to visible light), while at the same time, the surface of the spacecraft may be required to be thermally insulating (e.g., thermally non-conductive). The tuning techniques described above accommodate situations where a particular desired property (e.g., non-reflectiveness) takes priority over tuning a plasma spray torch to produce a substantially non-reflective surface, even at the expense of other properties.

[0344] The properties shown and described in connection with Figure 29 are merely exemplary. Additional properties and / or combinations of properties may be required or desired in various applications, and these additional properties may be exhibited in the resulting material based on adjustments to the inputs and controls of the plasma spray torch. Specifically, as examples of the aforementioned additional properties, such properties and / or combinations of properties may include or relate to strength-to-weight metrics, specific density, mechanical toughness, shear strength, bending strength, etc.

[0345] Some applications (e.g., high stress / high temperature operation, or operation in chemically harsh environments) have specific specifications regarding the corrosion resistance, and / or strength, and / or hardness, and / or other characteristics of the final material or component. In some situations, the specific specifications can be met by using alloys used to form the components for the specific application. VIM furnaces are often used to form the alloys. In some cases, carbon-containing materials in powder form are added to the alloy mixture to reduce weight while maintaining the strength and / or other characteristics of the alloy.

[0346] Unfortunately, VIM furnaces generate strong magnetic fields. The effect of these magnetic fields on the powder components is often stronger than the effect of gravity on the powder components. Therefore, the magnetic field has the undesirable effect of ejecting powder from the VIM furnace before the powder has a chance to enter the VIM furnace crucible, melt, and then disperse into the mixed melt. One technique to address this undesirable ejection of powder from the VIM furnace is to pelletize the powder into a dense form so that when the form is introduced into the VIM furnace, it is not ejected by the magnetic force of the VIM furnace. Rather, the pelletized form enters the VIM furnace crucible, where it melts inside the VIM furnace and is mixed into the molten mixture.

[0347] In this manner, a carbon-containing alloy is formed, preferably having at least some, and more preferably all, of the physical characteristics described herein above with respect to the Cobetic material. Such physical characteristics are understood to include, but are not limited to, a high carbon loading (e.g., greater than 1.5%, greater than 5%, greater than 15%, greater than 40%, greater than 60%, and up to 90% of the material being carbon, according to various embodiments), a substantially uniform distribution of carbon throughout the surface layer and / or bulk of the material, the presence of carbon in interstitial positions in the crystal lattice of the metal to which it is alloyed, and the absence of carbon aggregates and / or agglomerates at the grain boundaries of the material.

[0348] Figures 30A1 and 30A2 illustrate the problems and solutions associated with melting powdered metal-modified carbon compared to melting metal-modified carbon in pellet form. These figures are presented side by side to specifically illustrate the problems (30A100) and solutions (30A200) associated with using powder in a VIM processor.

[0349] As known in the art, vacuum induction melting relies on a high-power current source 3006 to melt metal within a vacuum environment 3002. The induction heating process generates eddy currents within the conductor (e.g., metal). The eddy currents then generate heat. The magnetic field generated by the heating coil generates an upward force. Each individual particle of powder 3004 is not heavy enough to overcome the upward force generated by the electromagnetic force, resulting in undesired ejection 3003 of the metal-modified carbon powder. Figure 30A2 illustrates a solution disclosed herein to this undesired ejection, namely, by compressing many individual particles of powder into a pellet 3008. As a result, the force of gravity acting on the pellet exceeds the force of the magnetic field on the powder's components. This solves the previously discussed problem of the VIM processor's magnetic field being stronger than the effect of gravity on the powder. The pellet then enters the crucible and is heated along with the components of the mixture.

[0350] Once the mixture reaches its melting point, a magnetic field begins to stir the metal alloy. The alloy melt (with the carbon-containing components dispersed throughout the alloy melt matrix) can be poured into component-specific molds for a given application.

[0351] 31 illustrates a method of using pellets 3108 to minimize or eliminate material ejection during introduction of the pellets 3108 into a VIM processor 3110. The figure is presented to illustrate an exemplary material processing process in which powder material 3004 is pelletized before being used in the VIM processor. In additional approaches, the VIM processor 3110 may be replaced with or used in combination with a vacuum arc melting processing device, an electron beam melting furnace, an ion plating furnace, a plasma flame source, a smelting furnace, a conventional metal-metal melting furnace, or any equivalent(s) and / or combination thereof as would be understood by one of ordinary skill in the art upon reading this disclosure.

[0352] To obtain the powder material, a feed gas (e.g., a hydrocarbon such as methane) is flowed into a plasma reactor to generate a plasma containing dissociated carbon and hydrogen atoms. At certain locations within the plasma plume, e.g., where hydrogen has completely dissociated from the carbon atoms, a metal melt (e.g., nickel melt) is injected into the plasma. The injected metal melt combines with the dissociated carbon atoms to form metal-modified carbon molecules, some of which fuse with other metal-modified carbon molecules. Upon cooling to a temperature below the melting point of the injected metal, the precipitate is released from the plasma reactor as powder material 3104.

[0353] After collecting the metal-modified carbon powder from the plasma reactor (step 3114), the metal-modified carbon molecules are separated from the dissociated hydrogen molecules (e.g., H) in a gas-solid separator or other collection vessel, optionally located at the outlet port of the plasma reactor. For example, as shown, gas-solid separator vessel 3102 can be implemented using equipment such as a gravity separator, cyclone, scrubber, electrostatic separator, filter, etc., as would be understood by one of ordinary skill in the art upon reading this disclosure.

[0354] In the example shown, metal-modified carbon (solid) and hydrogen molecules (gas) can be placed in a cyclone gas-solid separator vessel 3102. This particular configuration uses the concept of inertia to separate solids (e.g., metal-modified carbon) from gases (e.g., hydrogen). Due to the difference in molecular weight between the metal-modified carbon and hydrogen, the lighter material (in this case, hydrogen) is more susceptible to the vortex created within the cyclone gas-solid separator vessel. Thus, the hydrogen gas is forced to move upward (via the cyclone effect), thereby separating the gas from the heavier powder material 3104 (e.g., metal-modified carbon molecules). The shape of the gas-solid separator vessel facilitates downward flow of the metal-modified carbon particles toward the bottom of the vessel. This downward flow is opposite to the upward flow of the hydrogen. Thus, the metal-modified carbon particles can be collected for further processing.

[0355] Once the metal-modified carbon powder is isolated from and captured by the hydrogen, the metal-modified carbon is compressed to form rigid pellets 3108 (step 3116). This pelletization may be achieved through the use of a pelletizer 3106, such as, for example, a 12-ton press, which may be automatically operated or manually operated. While this example shows the use of a 12-ton press as the pelletizer 3106, any pelletizing technique and / or equipment that would be understood by one of ordinary skill in the art, once apprised of this disclosure, as being suitable for producing pellets having sufficient mass to avoid discharge from a VIM processor may be used without departing from the scope of the present invention.

[0356] Pelletization of metal-modified carbon takes advantage of the dynamics of how metal-modified carbon interacts with the magnetic flux of the VIM relative to gravity. More specifically, gravity acts more strongly on pellets than magnetic flux. Therefore, when pellets (rather than powder) are introduced into the VIM processor 3110, the aforementioned problems with material ejection due to magnetic forces are eliminated.

[0357] Once the pellets are introduced into the crucible of the VIM processor, they melt and begin to mix with the other contents of the crucible (step 3118). During this step, as the pellets melt, they become uniformly dispersed within the metal mixture. To promote uniform dispersion, according to various embodiments, the VIM crucible can be filled with only pellets, with the pellets positioned above the metal powder, or with the metal powder positioned both below and above the pellets.

[0358] The resulting melt 3112 may then be poured into a mold (step 3120) and / or used in conjunction with injection molding equipment to form a component (e.g., a turbine blade, an automotive component, a medical device, etc.) In some cases, the output of the VIM processor (e.g., melt 3112) is cooled and then powdered using any suitable technique for use in other mechanical part formation methods, e.g., 3D printing, or further use in any application (step 3122).

[0359] 32 shows a melt 3112 placed into a mold 3202. The melt 3112 can be placed into the mold 3202 of any shape or form. Once the melt has cooled, the component can be removed from the mold and used in its intended application.

[0360] Strictly speaking, as one example, a turbine blade mold can be used. A melt consisting of the metal mixture and the carbon-containing component can then be placed into the turbine blade mold and cooled. The turbine blade can be cooled, removed from the mold, and used for its intended application. As another example, the melt can be cooled, then powdered, and then packaged for use in a 3D printer or other additive manufacturing technique / device.

[0361] FIG. 33 shows simplified schematic diagrams of pellet processing according to various approaches. As described in detail above with reference to FIG. 31, powder material 3104, for example, obtained upon discharge from a microwave plasma reactor, is separated from undesired gases, and compressed into pellets using a pelletizer 3106. Preferably, pelletizer 3106 includes a die having a physical configuration / arrangement suitable for producing pellets having a desired shape. As shown in FIG. 33, die 3106a is configured to produce substantially cylindrical pellets (or "pucks") approximately one centimeter in diameter. Of course, those skilled in the art will understand that the geometric characteristics of the pellets can be selected and / or tailored based on the characteristics (e.g., magnetic field strength, volume, etc.) of the VIM processor (or equivalent device) used to produce the desired material. Notably, the pellets produced according to the experiment shown in FIG. 33 were produced without the need for chemical binders.

[0362] As shown in Figure 33 and demonstrated experimentally, the inventors have successfully produced pellets consisting essentially of intrinsic graphene (3108a), as well as pellets formed from metal-modified carbon, e.g., modified graphene (3108b). Both types of pellets can be produced using essentially the same techniques, the only difference being the composition of the powder used to produce the pellets.

[0363] In the experiment shown schematically in Figure 34, pellets, e.g., pellet 3108, were dispersed in an isopropanol solution by manual agitation. As will be understood by those skilled in the art upon reading this disclosure, after agitation, which may be performed manually, such as with an ultrasonic wand (or other mechanism for ultrasonic agitation), the resulting suspension exhibited permeability. Magnetic testing demonstrated dispersion of the nickel-modified carbon.

[0364] Inventive Concept Various embodiments, aspects, features, advantages, implementations, configurations, arrangements, etc. of the inventive concepts have been described hereinabove with reference to the various Figures. It is to be understood that, unless otherwise stated herein, such embodiments, aspects, features, etc. can be combined or modified in any suitable manner as would be understood by one of ordinary skill in the art upon reading this disclosure, without departing from the scope thereof. For complete clarity, the following inventive concepts are some of the preferred features, configurations, etc. of the inventive concepts presented herein, which can be utilized in any suitable manner, combination, or permutation while remaining within the scope of the disclosed invention.

[0365] According to one embodiment, a composition includes one or more particles, at least some of which independently comprise a metal lattice having one or more coherent planar layers of graphene arranged within the metal lattice. At least some carbon atoms of the one or more coherent planar layers of graphene are arranged in interstitial positions within the metal lattice. For example, the one or more coherent planar layers of graphene may be partially or completely interstitially interdigitated between the basal planes of the metal lattice. Preferably, the metal lattice comprises about 15% to about 90% by weight of carbon, and about 15% to about 60% by weight of the carbon in the particles is present in the interstitial positions. Furthermore, in some approaches, the metal lattice is characterized by a crystal structure selected from face-centered cubic (FCC), body-centered cubic (BCC), and hexagonal close-packed (HCC). In some approaches, the one or more coherent planar layers of graphene consist of a monolayer of graphene. Alternatively, the one or more coherent planar layers of graphene include at least five layers of graphene and no more than 15 layers of graphene. According to selected implementations, the one or more coherent planar layers of graphene are each independently substantially free of defects. The metal lattice may include one or more metals selected from the group consisting of aluminum, copper, iron, nickel, titanium, tantalum, tungsten, chromium, molybdenum, cobalt, manganese, niobium, and combinations thereof. For example, the metal lattice may be or include an Inconel alloy, which may be a superalloy formed from one or more metals selected from the group consisting of nickel, chromium, aluminum, copper, iron, titanium, tantalum, molybdenum, cobalt, manganese, and niobium. Furthermore, the Inconel alloy may be selected from the group consisting of Inconel 600, Inconel 617, Inconel 625, Inconel 690, Inconel 718, and Inconel X-750. At least some carbon atoms of the one or more layers of graphene are preferably covalently bonded to metal atoms of the metal lattice. More preferably, the covalent bond between the carbon atom of the graphene and the metal atom comprises a non-polar covalent bond.Similarly, at least some carbon atoms in one or more layers of graphene may be covalently bonded to other carbon atoms in one or more layers of graphene, and some or all of the covalent bonds between carbon atoms in graphene may include non-polar covalent bonds. Continuing with reference to bonds within the composition, one or more particles may completely or substantially exclude polar covalent bonds. Furthermore, the metal lattice of each of the one or more particles may substantially or completely exclude ionic bonds. "Substantial" exclusion should be understood to refer to a composition in which any polar, ionic, or other referenced type of bond present in the composition does not affect, or has a negligible effect on, the structural, physical, and functional characteristics of the composition. The particles may be characterized by a lack of carbon aggregate(s) and / or agglomerates at their grain boundaries, a diameter ranging from about 20 nm to about 3.5 μm, being compressed into pellets, or any combination of these characteristics. According to certain embodiments, the maximum distinguishable feature size of the composition is in the range of about 0.1 nm to about 1 μm. The particles may be compressed into pellets.

[0366] In the foregoing specification, the present disclosure has been described with reference to specific implementations thereof. However, it will be apparent that various modifications and changes can be made thereto without departing from the broader spirit and scope of the present disclosure. For example, the process flows described above are described with reference to a particular order of process actions. However, the order of many of the described process actions can be changed without affecting the scope or operation of the present disclosure. The specification and drawings are to be considered in an illustrative sense, and not in a restrictive sense.

Claims

1. 1. A composition of matter comprising one or more particles, at least a portion of which independently comprise a metal lattice, the metal lattice having one or more coherent planar layers of graphene disposed within the metal lattice.

2. 10. The composition of claim 1, wherein at least some carbon atoms of one or more coherent planar layers of graphene are positioned at interstitial sites within the metal lattice.

3. 10. The composition of claim 1, wherein one or more coherent planar layers of graphene are interstitially interdigitated between the basal planes of the metal lattice.

4. 10. The composition of claim 1, wherein the metal grid comprises one or more metals selected from the group consisting of aluminum, copper, iron, nickel, titanium, tantalum, tungsten, chromium, molybdenum, cobalt, manganese, niobium, and combinations thereof.

5. 10. The composition of claim 1, wherein the one or more coherent planar layers of graphene consist of a monolayer of the graphene.

6. 10. The composition of claim 1, wherein the one or more coherent planar layers of graphene comprise at least 5 layers of the graphene and no more than 15 layers of the graphene.

7. 10. The composition of claim 1, wherein at least some carbon atoms of one or more layers of said graphene are covalently bonded to metal atoms of said metal lattice.

8. 8. The composition of claim 7, wherein the covalent bond between a carbon atom of the graphene and the metal atom comprises a non-polar covalent bond.

9. 10. The composition of claim 1, wherein at least some carbon atoms in one or more layers of the graphene are covalently bonded to other carbon atoms in one or more layers of the graphene.

10. 10. The composition of claim 9, wherein the covalent bonds between the carbon atoms of the graphene comprise non-polar covalent bonds.

11. The composition of claim 1 , wherein the one or more particles substantially exclude polar covalent bonds.

12. The composition of claim 1 , wherein the metal lattice of each of the one or more particles substantially eliminates ionic bonding.

13. 10. The composition of claim 1, wherein the one or more coherent planar layers of graphene are each independently substantially free of defects.

14. 10. The composition of claim 1, wherein each of the one or more particles independently comprises from about 15% carbon by weight to about 90% carbon by weight.

15. 10. The composition of claim 1, wherein the metal lattice comprises from about 15% to about 60% by weight of carbon in its interstitial positions.

16. 10. The composition of claim 1, wherein the metal lattice is characterized by a crystalline structure selected from face-centered cubic (FCC), body-centered cubic (BCC), and hexagonal close-packed (HCC).

17. 10. The composition of claim 1, wherein each particle is characterized by a lack of carbon aggregate(s) and / or agglomerate(s) at its grain boundaries.

18. 10. The composition of claim 1, wherein each of the one or more particles is characterized by a diameter ranging from about 20 nm to about 3.5 μm.

19. 10. The composition of claim 1, wherein the maximum distinguishable feature size of the composition ranges from about 0.1 nm to about 1 μm.

20. The composition of claim 1 , wherein the one or more particles are compressed into a pellet.

21. A composition comprising an Inconel alloy, said Inconel alloy having carbon disposed in a metal lattice of said Inconel alloy.

22. 22. The composition of claim 21, wherein the carbon is located at interstitial sites of the metal lattice.

23. 22. The composition of claim 21, wherein at least a portion of the carbon is covalently bonded to metal atoms of the metal lattice.

24. 22. The composition of claim 21, wherein at least some of the carbon atoms are covalently bonded to metal atoms of the metal lattice.

25. 25. The composition of claim 24, wherein the covalent bond between the carbon atom and the metal atom comprises a non-polar covalent bond.

26. 22. The composition of claim 21, wherein at least some of the carbon atoms are covalently bonded to other carbon atoms disposed in the metal lattice.

27. 27. The composition of claim 26, wherein the covalent bond between the carbon atoms comprises a non-polar covalent bond.

28. 22. The composition of claim 21, wherein polar covalent bonds are substantially eliminated.

29. 22. The composition of claim 21, wherein the metal lattice substantially eliminates ionic bonding.

30. 22. The composition of claim 21, wherein the metal grid is characterized by a carbon loading ranging from about 15% to about 90% by weight.

31. 22. The composition of claim 21, wherein the grain boundaries of the Inconel alloy are substantially free of carbon aggregates and / or agglomerates.

32. 22. The composition of claim 21, wherein the carbon is substantially uniformly distributed throughout the metal lattice.

33. 22. The composition of claim 21, wherein the maximum distinguishable feature size of the composition ranges from about 0.1 nm to about 1 μm.

34. 22. The composition of claim 21, wherein the Inconel alloy is a superalloy formed from one or more metals selected from the group consisting of nickel, chromium, aluminum, copper, iron, titanium, tantalum, molybdenum, cobalt, manganese, and niobium.

35. 22. The composition of claim 21, wherein the Inconel alloy is a superalloy selected from the group consisting of Inconel 600, Inconel 617, Inconel 625, Inconel 690, Inconel 718, and Inconel X-750.

36. A composition comprising a metal lattice, the metal lattice having at least about 15% by weight of carbon disposed within the metal lattice.

37. 37. The composition of claim 36, wherein at least a portion of the carbon is located in interstitial sites of the metal lattice.

38. 37. The composition of claim 36, wherein the grain boundaries of the composition are substantially free of carbon aggregate(s) and / or agglomerate(s).

39. 37. The composition of claim 36, wherein the metal grid comprises one or more metals selected from the group consisting of nickel, chromium, aluminum, copper, iron, titanium, tantalum, tungsten, molybdenum, cobalt, manganese, niobium, and alloys thereof.

40. 40. The composition of claim 39, wherein the one or more metals are present in the form of an Inconel superalloy.

41. 17. The composition of claim 16, wherein at least a portion of the carbon is covalently bonded to metal atoms of the metal lattice.

42. 42. The composition of claim 41, wherein the covalent bond between the carbon atom and the metal atom comprises a non-polar covalent bond.

43. 37. The composition of claim 36, wherein at least some of the carbon atoms are covalently bonded to other carbon atoms disposed in the metal lattice.

44. 44. The composition of claim 43, wherein the covalent bond between the carbon atoms comprises a non-polar covalent bond.

45. 37. The composition of claim 36, which substantially excludes polar covalent bonds.

46. 37. The composition of claim 36, wherein the metal lattice substantially eliminates ionic bonding.

47. 37. The composition of claim 36, wherein the carbon is substantially uniformly distributed throughout the metal lattice.

48. 37. The composition of claim 36, wherein the maximum distinguishable feature size of the composition ranges from about 0.1 nm to about 1 μm.

49. 37. The composition of claim 36, wherein the metal lattice is characterized by a crystalline structure selected from face-centered cubic (FCC), body-centered cubic (BCC), and hexagonal close-packed (HCC).

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