208 results about "Polycrystalline diamond" patented technology

The invention discloses a plasma rotation type large-area polycrystalline MPCVD diamond growth method, and relates to the technical field of microwave plasma chemical vapor deposition, and the method comprises the following steps: S1, setting environmental parameters of diamond growth in a reactor through a microwave feeder, sampling plasma state data in the reactor, and calculating the plasma state data; if the plasma is stably started, executing S2; and S2, the plasma state in the reactor is adjusted through the plasma regulator according to the plasma state data in the reactor, the coverage area of plasma discharge is increased, and then the growth area of the polycrystalline diamond is increased.

The invention discloses a superhard cutter surface micro-nano structure preparation method based on ultrafast laser and a cutter. The method comprises the steps that a polycrystalline diamond cutter is fixed to a three-axis precision motion platform and precisely positioned and calibrated; after cleaning and online detection, parameters of the ultrafast laser are configured based on a result, and machining is executed; and evaluating the structure characterization of the generated laser-induced periodic surface. According to the method, thermal damage is avoided by means of the ultrafast laser near-cold machining characteristic, parameters are precisely regulated and controlled, a high-precision structure is efficiently prepared, the process is flexible and controllable, the limitation of a traditional technology is broken through, the tool performance is improved, a scheme is provided for cutting of aerospace materials difficult to machine, and non-damage microtexture preparation on the surface of the superhard tool is achieved.

The invention relates to the technical field of superhard materials, and particularly discloses a polycrystalline diamond compact and a preparation method and application thereof.The preparation method of the polycrystalline diamond compact comprises the following steps that WC-Co alloy powder is sintered to obtain a hard alloy matrix; uniformly mixing nano diamond powder, micron diamond powder and cubic boron nitride, adding a reinforcing agent and a binding agent, and uniformly mixing to obtain a polycrystalline diamond layer mixture; the reinforcing agent is a nitrogen-boron doped graphene bonded amino carbon nanotube; a gradient transition layer raw material and a polycrystalline diamond mixture are uniformly spread on the surface of the hard alloy matrix in sequence, and then a composite blank is obtained through mold pressing; and sintering the composite blank to obtain the polycrystalline diamond compact. Graphene and carbon nanotubes are compounded to form a reinforcing agent with a three-dimensional network structure, so that the strength and wear resistance of the material are improved, and the service life of the material under harsh working conditions is prolonged.

The invention provides a diffusion welding method of a CoZrTaB target material, which comprises the following steps: (1) carrying out finish machining on a CoZrTaB target blank to a welding size, and processing a thread on a welding surface of the CoZrTaB target blank by adopting a polycrystalline diamond screwer; (2) first cleaning and PVD titanium film plating are sequentially carried out on the welding face with the machined threads, and a to-be-welded CoZrTaB target blank is obtained; the back plate is subjected to finish machining to the welding size, and a to-be-welded back plate is obtained; and (3) the to-be-welded CoZrTaB target blank and the to-be-welded back plate are sequentially subjected to second cleaning, assembling, sheath welding, high-temperature degassing and diffusion welding, and the diffusion-welded CoZrTaB target material is obtained. According to the diffusion welding method, the polycrystalline diamond screwer is adopted to machine the threads on the welding face of the CoZrTaB target blank, then the titanium film is plated, and the CoZrTaB target material which is high in welding strength and meets the high-temperature sputtering use requirement is obtained.

This application relates to a polycrystalline diamond composite substrate, belonging to the technical field of superhard material composites. It includes a cylinder with one end serving as a bonding surface; a frustum located at one end of the bonding surface, comprising a truncated cone coaxially transitioning onto the cylinder and a frustum coaxially connected to the truncated cone; and a raised structure disposed on the frustum, comprising multiple sets of coaxially arranged raised units, each set of raised units being evenly distributed in a ring around the center of the bonding surface, with grooves formed between adjacent raised units, the grooves being concentric with the bonding surface. This application allows external forces applied to the composite to be more evenly distributed across different parts of the substrate, avoiding localized stress concentration. The raised structure increases the contact area between the substrate and the diamond layer, significantly enhancing the adhesion between them. During drilling, the diamond layer adheres more firmly to the substrate, reducing the risk of premature detachment of the diamond layer due to external forces.

The present application relates to the preparation method of thick polycrystalline diamond compact for oil and gas drilling, which comprises the following steps: mixing two or more kinds of diamond powder with impurities removed; sand blasting the cemented carbide substrate; sequentially loading the impurity storage layer, the diamond powder mixture layer, the low-melting-point metal sheet, the cobalt sheet and the cemented carbide substrate into a high-temperature-resistant metal cup; placing the high-temperature-resistant metal cup into a synthetic block and then into a six-surface press; performing two-stage high-temperature and high-pressure sintering, wherein the first stage is sintering at a pressure of 5.5-5.8 GPa and a temperature of 800-1300 DEG C for 60-150 seconds, and the second stage is sintering at a pressure of 6-8 GPa and a temperature of 1490-1580 DEG C for 450-700 seconds; and taking out at room temperature and normal pressure. The impurity storage layer, the low-melting-point metal sheet and the cobalt sheet are arranged, and the high-temperature and high-pressure scanning sintering method is adopted, so that the thickness of the diamond layer reaches 3-4 mm after sintering, and the service life is greatly prolonged.

The present invention relates to highly pure high performance polycrystalline diamond monolith, a method for manufacturing a single-crystal diamond, and uses thereof.

The invention belongs to the field of preparation of wide bandgap semiconductor materials, and particularly discloses a preparation method of a low-stress large-size polycrystalline diamond wafer, which comprises the following steps: by taking a substrate as a growth foundation of diamond, sequentially carrying out diamond inoculation treatment and MPCVD process treatment on the substrate so as to grow and form an initial growth layer on the substrate; the primary growth layer serves as a growth foundation of diamond, diamond inoculation treatment and MPCVD process treatment are sequentially conducted on the primary growth layer, a secondary growth layer is formed on the primary growth layer in a growing mode, and an elastic buffer interface is formed between the primary growth layer and the secondary growth layer. By means of the method, the problems of wafer warping, film layer microcracks and film layer stripping caused by the residual stress of the large-size wafer can be solved, active reconstruction and release of the residual stress are facilitated through the successive multiple inoculation and growth processes, and then preparation of the polycrystalline diamond wafer with low stress, large size and high crystallization quality is achieved.

The invention discloses polycrystalline diamond defect detection and repair equipment and an intelligent repair method. The method comprises the following steps: preprocessing a to-be-processed area of a to-be-detected product, performing excitation scanning, obtaining distribution data of an internal fluorescence signal, and generating a fluorescence signal distribution diagram; carrying out image analysis on the fluorescence signal distribution diagram, identifying and positioning an abnormal fluorescence signal region in the fluorescence signal distribution diagram, constructing a three-dimensional coordinate model according to the abnormal fluorescence signal region, and processing by adopting ultra-short pulse laser processing equipment to form a repair channel; providing a repair alloy, and filling the repair alloy into the repair channel through a directional infiltration technology to realize metallurgical bonding repair of the internal defect area; an optical traceable signal detection mechanism is introduced into a polycrystalline diamond material, and an ultrashort pulse laser micro-channel processing and directional infiltration repairing process is combined, so that positioning and in-situ repairing of internal defects are realized, and the overall mechanical property of the material is effectively recovered; therefore, the service life of the product is obviously prolonged, and the machining reliability is improved.

This invention belongs to the field of superhard material synthesis technology, specifically disclosing a high-temperature, high-pressure preparation method for nano-polycrystalline diamond with synergistic mechanical and thermal properties. The method includes the following steps: precursor preparation: pre-pressing the precursor in a cemented carbide mold; octahedral assembly; wrapping the pre-pressed sample with platinum foil and placing it at the center of the octahedron; high-temperature, high-pressure sintering; stopping heating after heat preservation, allowing it to cool naturally to 23-25°C, then depressurizing, removing the octahedral assembly and the platinum foil wrapping, thus obtaining the synergistically enhanced nano-polycrystalline diamond. This invention employs the above-mentioned high-temperature, high-pressure preparation method for nano-polycrystalline diamond with synergistic mechanical and thermal properties. By combining nanodiamond powder with graphene, the sample assembly is optimized, and nano-polycrystalline diamond samples with excellent mechanical properties and significantly improved thermal conductivity are synthesized under relatively mild temperature and pressure conditions.

The present application provides a kind of micro-nano heterogeneous polycrystalline diamond compact and its preparation method, drill bit.The micro-nano heterogeneous polycrystalline diamond compact includes hard alloy substrate and micro-nano heterogeneous polycrystalline diamond layer arranged on the hard alloy substrate;Wherein, micro-nano heterogeneous polycrystalline diamond layer includes micron diamond microcrystal and nanometer polycrystalline diamond microcrystal.The micro-nano heterogeneous polycrystalline diamond compact introduces the internal structure for nanometer polycrystalline diamond into the traditional polycrystalline diamond layer to replace the original part of micron diamond, can reduce the cobalt content in polycrystalline layer, improve the heat resistance of compact, in addition, since the nanometer polycrystalline diamond with higher hardness, toughness than traditional micron diamond is added, the hardness, wear resistance and impact resistance of polycrystalline diamond compact are improved.

This application relates to the field of superhard materials technology, specifically disclosing a method for preparing polycrystalline diamond composite sheets and their application in drill bits. The method for preparing the polycrystalline diamond composite sheet includes the following steps: S1, molding and sintering WC powder and Co to obtain a cemented carbide substrate; S2, grafting multi-walled carbon nanotubes with free radicals to obtain modified multi-walled carbon nanotubes; S3, surface-treating diamond micropowder to obtain modified diamond micropowder; S4, processing the modified diamond micropowder, modified multi-walled carbon nanotubes, N-rGO, Ti powder, etc., to obtain a powder, which is then combined with the cemented carbide substrate to obtain the polycrystalline diamond composite sheet. This application uses modified diamond and composite reinforcing phases to solve the problems of weak interfaces and thermal stress concentration within the polycrystalline diamond composite sheet, while simultaneously improving structural integrity and impact resistance at high temperatures.

The invention discloses a method for eliminating internal stress of a large-scale polycrystalline diamond block material. The method comprises the following steps that the block material is placed in a vacuum heat treatment furnace; carrying out vacuumizing and gas washing operation on the furnace chamber so as to remove residual active gas; introducing high-purity protective gas into the furnace and maintaining positive pressure; executing a stepped heating and heat preservation process: firstly, heating to a first heat preservation temperature T1 at a first heating rate and preserving heat, and then heating to a higher second heat preservation temperature T2 at a second heating rate and preserving heat; and after heat preservation is completed, the controlled cooling process is executed till the furnace temperature is reduced to the room temperature. A strategy of'stepped heating + long-time heat preservation 'is adopted, firstly, the stress of a part of a high-energy area is preliminarily relaxed at a low temperature T1, and cracking caused by stress concentration due to rapid heating is avoided; then, at a higher temperature T2, sufficient energy is provided for atomic diffusion and grain boundary slippage, and deep and uniform release of the internal stress is achieved. And the method is particularly suitable for large-scale blocks.

A superabrasive compact and a method of making the superabrasive compact are disclosed. A superabrasive compact may comprise a diamond body and a metallic substrate. The diamond body comprises diamond particles. Diamond particles may have a plurality of layers of inorganic hard coatings on surface of diamond particles. The plurality of layers of coatings may have thickness ranging from about 0.1% to about 20% of the size of the diamond particle. The metallic substrate may be in direct contact with the diamond body.

A novel diamond composite cutting tooth comprises a cutting tooth base body and a diamond tooth tip, a main body of the diamond tooth tip is a hard alloy conical base body, a diamond polycrystalline layer is arranged on the side face of the conical tip of the conical base body, a circular truncated cone part is arranged at the tip end of the cutting tooth base body, a groove is formed in the center of the end face of the circular truncated cone part, and the diamond tooth tip is embedded in the groove. The polycrystalline diamond layer is located outside the groove, a plurality of protection body grooves are evenly distributed in the side face of the circular truncated cone part, and protection body composite sheets are installed in the protection body grooves; the diamond tooth top of the composite cutting tooth is fixed in the groove of the cutting tooth base body in an embedded mode, thermal damage to the diamond tooth top caused by traditional brazing is avoided, the mechanical property of the diamond tooth top is improved, the diamond tooth top is of a composite structure formed by combining the hard alloy conical base body and the diamond polycrystalline layer, and the service life of the composite cutting tooth is prolonged. The diamond composite cutting pick has high wear resistance of diamond and excellent impact toughness of hard alloy, the probability of impact failure of a diamond tip is reduced, the advantage of high wear resistance of polycrystalline diamond is exerted, and the service life of the diamond composite cutting pick is prolonged.

The polycrystalline diamond multi-point cutting drill bit for the down-the-hole hammer comprises an installation base body, a drill bit handle is coaxially arranged at the top of the installation base body, a plurality of movable grooves are symmetrically formed in the edge of the bottom of the installation base body, a blocking face is arranged at one end in each movable groove, and an installation block body is contained in each movable groove. The ends, close to the blocking faces, of the installation block bodies are rotationally connected with the movable grooves, all the installation block bodies can rotate to the exterior of the installation base body, at the moment, the installation block bodies are all arranged on the blocking faces, and a plurality of polycrystalline diamonds are arranged on the bottom faces of the installation block bodies and the installation base body. When the drill bit is used, the mounting block body extends to the outside of the mounting seat body when the drill bit is forwards tunneled, so that the tunneled diameter of the mounting seat body can be enlarged, and when the drill bit is lifted and the mounting seat body is reversely rotated, the mounting block body can automatically rotate into the movable groove, so that the diameter of the drill bit is reduced, and the drill bit can be conveniently pulled out of a hole.

This invention relates to a method for preparing polycrystalline diamond (PCD) preforms and a method for preparing PCD, belonging to the field of PCD technology. The method for preparing PCD preforms of this invention involves isostatic pressing of PCD raw material powder, which effectively reduces porosity within the PCD preform, improves the uniformity of density distribution within the preform, and reduces residual stress within the preform. When using the PCD preform prepared by this invention to prepare PCD, defects such as cracks and fissures on the surface of the PCD can be effectively reduced, improving the surface quality of the PCD and thus increasing the production yield. Furthermore, it can improve the wear resistance and impact toughness of the PCD.

This invention discloses a rapid, non-destructive method for determining the deformation of polycrystalline diamond (PCD), comprising the following steps: Step 1: Grinding the surface of the PCD material using a grinding machine until the polycrystalline diamond layer is completely exposed; Step 2: Placing the polycrystalline diamond layer of the PCD material onto a surface grinding machine and grinding the upper side of the PCD material using the surface grinding machine; Step 3: Preliminarily processing the PCD material using the surface grinding machine to expose alloy layer 1, with the exposed point as the starting point; Step 4: Processing the PCD material again using the surface grinding machine until the cup covering the upper side of the PCD material is completely removed, with that point as the ending point. This invention allows for rapid deformation detection on the production line and is applicable to the deformation detection of gradient materials and heterogeneous materials with double or multi-layer structures. It changes the current situation where cutting profile measurements are required outside the production line, or ultrasonic testing is only applicable to homogeneous materials, facilitating the detection of PCD materials and improving detection accuracy.

The invention relates to the technical field of superhard material preparation, in particular to the related technical field of cobalt-free diamond compacts. The Ni-Cr binding agent cobalt-free diamond compact comprises a base body and a polycrystalline diamond layer, the base body is prepared from, by weight, 85-95 parts of WC, 5-13 parts of Ni and 0.4-2 parts of Cr, and Ni and Cr in the base body are distributed in gaps of WC grains; according to the Ni-Cr binding agent cobalt-free diamond compact, the wear resistance and heat resistance of the diamond compact can be improved, and meanwhile the binding strength between a polycrystalline diamond layer and a base body is enhanced.

The application discloses a cutter and a preparation method thereof. The cutter comprises a cutter head with a cutter tooth, the cutter head has a porous structure, a polycrystalline diamond film is arranged on the surface of the cutter tooth and the arc surface around the cutter tooth respectively, the polycrystalline diamond film comprises a transition layer extending into the porous structure and a superhard film layer on the surface of the transition layer, the transition layer comprises nanoscale polycrystalline diamond crystals, and the superhard film layer comprises microscale polycrystalline diamond crystals. The polycrystalline diamond film is formed on the surface and around the cutter tooth, the hardness, wear resistance and shock resistance of the cutter head are improved, the service life of the cutter is prolonged, the manufacturing cost is reduced, high-speed milling of the cutter is realized, and the machining efficiency is improved.

The invention discloses a method for preparing spherical or sphere-like polycrystalline diamond through chemical vapor deposition and a product thereof, and belongs to the technical field of artificial diamonds.The method comprises the steps that 1, a sheet is provided, and nano particles are arranged on the surface of the sheet to serve as nucleation points; (2) taking a sheet with nano particle nucleation points on the surface as a base material, firstly raising the temperature of the base material to 700-1200 DEG C by utilizing a chemical vapor deposition method, then introducing hydrogen and methane into the reaction cavity according to the volume flow ratio of the methane to the hydrogen being (1-7): 100, and depositing to form spherical or sphere-like polycrystalline diamond; and (3) separating the spherical or spheroidic polycrystalline diamond from the surface of the base material treated in the step (2), and further purifying to obtain the product spherical or spheroidic polycrystalline diamond powder. The method provided by the invention has the advantages of precise control of diamond particle size and maintenance of good sphericity, and the obtained spherical or spheroidic polycrystalline diamond is micron-sized, adjustable in size, high in sphericity and good in uniformity.

The present application relates to the technical field of crystal growth, in particular to a seed crystal arrangement device and method for CVD polycrystalline diamond growth. The device comprises a strong electric field coating device, which comprises an upper electrode plate and a lower electrode plate, the upper electrode plate being arranged directly above the lower electrode plate; a CVD polycrystalline diamond epitaxial substrate with adhesive is fixed to the lower surface of the upper electrode plate, and a non-metal plate is arranged on the upper surface of the lower electrode plate; a static high-voltage generator is connected to the lower electrode plate, and the upper electrode plate is grounded. The diamond powder and the CVD polycrystalline diamond epitaxial substrate are placed in the strong electric field coating device, the strength of the electrostatic field is matched according to the particle size, the voltage of the static high-voltage generator is 50,000-120,000 volts; the hydrogenated diamond powder forms a dipole moment under the strong electrostatic field, and is adsorbed onto the CVD polycrystalline diamond growth substrate from the lower part under the action of the Lorentz force, realizes the embedding of the conical bottom surface into the glue during the movement, the tip is outward, realizes the uniformity and consistency of the seed crystal arrangement; the device has a simple structure and a reasonable design.

This invention discloses a single-crystal diamond and its preparation method, relating to the field of inorganic materials. In preparing the single-crystal diamond, a seed crystal with a (100) crystal plane is selected, polished, and then etched to obtain a pretreated seed crystal. A single-crystal diamond base layer is grown on the surface of the pretreated seed crystal to obtain a diamond with a base layer. The diamond with the base layer is cut, grown in a nitrogen-containing environment, annealed, and finally coated with silicon to obtain the single-crystal diamond. The single-crystal diamond obtained by this invention can provide a clean and regular "starting point" for growth by pre-removing the edge regions with poor initial growth quality, fundamentally avoiding the problem of polycrystalline diamonds starting from the original edge and rapidly enveloping the surface, thereby effectively suppressing edge parasitic deposition. Simultaneously, nitrogen doping and finally silicon coating on the surface result in superior electrical properties.

The application discloses an integration method of a lithium niobate-indium phosphide photoelectric integrated device based on a diamond substrate, which directly bonds a polycrystalline diamond substrate with the integrated chip, effectively improves the heat dissipation effect without affecting the original device performance, and solves the heat mismatch problem of lithium niobate, indium phosphide and other materials in the hetero-integration, and the whole preparation process is completed under low-temperature conditions, a heat mismatch balance temporary adhesive layer is introduced, and a low-temperature and long-time annealing treatment is combined, so that the bonding strength is improved, the interface thermal resistance is reduced, and the damage of the thin film material caused by the heat mismatch is reduced or eliminated; the method does not introduce more processes or complex designs except the bonding process, helps to ensure the process consistency, and realizes the transfer of the multi-layer hetero-wafer material and the prepared device layer.

The application provides a chemical vapor deposition polycrystalline diamond steel liquid erosion polishing method and relates to the technical field of diamond material processing. The chemical vapor deposition polycrystalline diamond steel liquid erosion polishing method places steel material with a carbon content of 0-0.77% and a weight of 0.1-5 kg in a ceramic crucible, uses inductive coupling to heat the steel material to 1400-1800 DEG C and controls the liquid surface to be stable, uses a motion controller with a moving control precision of not more than 0.02 mm to immerse the sample in the steel liquid for 0.1 s-10 min and then take out the sample, and carbon atoms constituting the sample are dissolved and diffused into the steel liquid under the action of the steel liquid erosion, so that the sample surface is rapidly flattened. The method has the advantages that a new way is provided for realizing high-speed, high-yield and high-throughput polishing processing of chemical vapor deposition polycrystalline diamond.

The application discloses a preparation method of a synthesis column for polycrystalline diamond synthesis, which adopts a wet mixing method of a composite mixing medium to improve mixing efficiency and mixing uniformity, reduces mixing time from 15 hours to 4 hours or below, and saves time cost; meanwhile, the supercritical CO2 extraction drying and atmosphere furnace reduction technology are adopted for the first time, the water removal rate is increased by 5-8% compared with a conventional drying method, the oxygen between the gaps of the particles is further replaced, the oxidation layer of the catalyst surface layer is further treated, the influence of the oxidation layer of the catalyst surface on the nucleation and growth of the diamond is reduced, and the yield of the polycrystalline diamond is further increased.

This application relates to an apparatus and method for mass production of large-size polycrystalline diamond wafers, belonging to the field of diamond wafer fabrication technology. An apparatus for mass production of large-size polycrystalline diamond wafers includes: a reaction chamber, reaction components, and a second heating filament assembly. The reaction component includes a first heating filament assembly and a substrate stage. Multiple sets of reaction components are spaced horizontally within the reaction chamber. The axes of the first and second heating filament assemblies are both vertically oriented. The axis of the substrate stage is horizontally oriented. The first and second heating filament assemblies are parallel to the substrate stage. The substrate stage includes a fixing ring, which includes an annular mounting portion in the middle along the axial direction for securing the peripheral wall of the substrate. Annular eaves are located on both sides of the annular mounting portion along the axial direction of the fixing ring. This method can produce diamonds more uniformly and in larger quantities, improving the problem of diamond warping and even cracking.

The invention provides a method for growing and stripping polycrystalline diamond with low stress, the principle of the method is that the characteristic that a substrate and a transition layer are low in mismatch with the polycrystalline diamond is utilized, and meanwhile, the substrate is etched by hydrogen after the polycrystalline diamond grows by utilizing the strong etching capability of the hydrogen, so that the intervention of extra stress is avoided, and the polycrystalline fracture is reduced. Compared with the prior art, the scheme can effectively reduce the breakage of the polycrystalline diamond during stripping, and can be applied to solve the problem of low yield caused by breakage of the industrial MPCVD polycrystalline diamond.

The utility model relates to the technical field of coal mining, and discloses a polycrystalline diamond tunneling tooth which comprises a tooth handle, a tooth table is fixedly connected to the top end of the tooth handle, an installation cover is arranged at the top end of the tooth table, a tooth tip is arranged on the inner wall of the tooth table, a limiting ring is fixedly connected to the outer wall of the tooth tip, and limiting assemblies are arranged at the four corners of the inner wall of the tooth table. The limiting assembly comprises fixing blocks located at the four corners of the inner wall of the tooth table in a sliding connection mode, the bottom ends of the fixing blocks are fixedly connected with sliding blocks, the sliding blocks are connected with the inner wall of the tooth table through springs, and fixing assemblies are arranged at the four corners of the inner wall of the mounting cover. According to the utility model, when the tooth tip on the mounting cover is fixed on the tooth table through the bolt, the fixing block can be pushed to move inwards, the tooth tip is further fixed, the fixing effect is improved, and the tooth tip can be conveniently taken out and conveniently replaced by screwing out the bolt, so that the maintenance cost is reduced, and the use of people is facilitated.