12results about How to "Overcoming brittleness" patented technology

The invention relates to the technical field of bulletproof armor, in particular to a bionic ceramic armor module and a preparation method thereof. The bionic ceramic armor module comprises a plurality of ceramic bulletproof layers and nano energy-absorbing adhesive bonding layers which are stacked in a staggered mode, each ceramic bulletproof layer comprises a plurality of ceramic pieces, the ceramic pieces are arranged in order in an array mode, the ceramic pieces are tightly bonded through pouring of nano energy-absorbing adhesives to form single thin layers, and the single thin layers are sequentially stacked in a staggered mode; nano energy-absorbing glue is sprayed between every two layers of the single thin layers to form a nano energy-absorbing glue bonding layer, and the ceramic bulletproof layer and the nano energy-absorbing glue bonding layer form a composite whole. The bionic ceramic armor module is rigid and flexible, good in toughness, high in energy absorption density and light in weight, and the multi-time anti-penetration capacity is greatly improved. Different modules with different layer numbers, thicknesses, hardness, weights, size specifications and anti-penetration strengths can be programmed and designed according to actual purposes, and the application range is wide.

The invention relates to a preparation method and application of a multifunctional needled glass fiber aerogel felt. The invention discloses a multifunctional needled glass fiber aerogel felt which is prepared by the following steps: adding a catalyst, tetraethyl orthosilicate, ethanol and deionized water into a beaker in parts by weight, uniformly stirring, putting the needled glass fiber felt into a solution, aging, drying and modifying to finally obtain the needled glass fiber aerogel felt, and the catalyst is ammonia water or hydrochloric acid. The needled glass fiber aerogel felt not only can play a role in heat insulation and fire prevention, but also can absorb sound and reduce noise, and is a multifunctional high-quality material.

The invention discloses a flexible conductive drivable composite fiber and a preparation method, system and application thereof. The preparation method comprises the following steps: uniformly mixing a polymer solution with a large thermal expansion coefficient, a curing agent and a diluent to form a diluted polymer solution; the preparation method comprises the following steps: immersing conductive fibers in a diluted polymer solution, and then enabling a polymer to enter a conductive carbon fiber tow under the extrusion action through a rolling mechanism, and carrying out first-time immersion and homogenization; then dipping in a pure polymer solution, and carrying out capillary homogeneous extrusion again through the rolling mechanism; the operation is repeated for more than two times, so that the pure polymer solution is uniformly distributed in the conductive fiber tows; and finally, curing and twisting to prepare the flexible conductive drivable composite fiber with the uniform spiral structure. The composite fiber with a uniform structure is prepared through a rolling-assisted step-by-step impregnation process, has certain flexibility, retains good mechanical properties of the fiber, and still has good mechanical properties after knotting and spiral deformation.

This invention relates to the field of insulating materials for porous copper foil preparation, and particularly to an insulating material for porous copper foil preparation and its preparation method, as well as a method for preparing porous copper foil. The preparation method includes the following steps: perforating a cathode plate to obtain a cathode plate with multiple blind holes; filling the blind holes with an insulating material for porous copper foil preparation, and curing it to obtain a pretreated cathode plate; the raw materials for the insulating material are: resin, reactive diluent, thixotropic agent, leveling agent, polymerization inhibitor, and photoinitiator. The pretreated cathode plate is used as the cathode and placed in an electrolyte for electrodeposition to obtain porous copper foil. When preparing porous copper foil with the insulating material, the filling material in the blind holes can withstand more than 80 electroplating cycles without peeling off, indicating that the insulating material for porous copper foil preparation possesses excellent adhesion and electrolyte environment durability, enabling a single-filled cathode to support stable electrodeposition over an ultra-long period, significantly extending its effective service life.

The application relates to the technical field of ceramic materials, and particularly discloses a high-temperature-resistant silicon carbide composite ceramic material and a preparation method. The composite ceramic material comprises, from inside to outside, an interface modification framework, a structural matrix layer and a protective matrix layer; the interface modification framework is prepared by impregnating and calcining a bifunctional modified carbon fiber web with a titanium-aluminum precursor sol; the structural matrix layer is prepared by impregnating an inner layer slurry into the interface modification framework and solidifying; the protective matrix layer is prepared by coating a surface layer slurry on the surface of the structural matrix layer and solidifying; and the inner layer slurry and the surface layer slurry are both prepared from polycarbosilane precursors, modified silicon carbide and anhydrous toluene. Through the synergy of multiple weak interface toughening, precursor molecular-level hybrid self-repairing and gradient densification processes, the inherent brittleness of the ceramic is overcome, and the fracture toughness and super-high-temperature oxidation resistance of the material are improved.

The application discloses a high-pressure die-casting motor rotor casting aluminum alloy and a preparation method thereof, and belongs to the technical field of motor rotor materials. The high-pressure die-casting motor rotor casting aluminum alloy comprises the following components in percentage by mass: Mg 0.75-0.85 wt%, Fe 0.15-0.25 wt%, Ti≤0.03 wt%, Ga≤0.03 wt%, Zn≤0.03 wt%, Cu≤0.03 wt%, Mn≤0.01 wt%, Si≤0.01 wt%, other impurities≤0.35 wt%, and the balance of Al. The type of elements and the percentage by mass of each element are specifically limited, the percentage by mass of Si is reduced, the influence of Si on the electrical conductivity of the aluminum alloy is reduced, the electrical conductivity of the aluminum alloy is improved to a certain extent, the percentage by mass of Mg and Fe is limited, Mg forms a solid solution in Al, Fe interacts with Al to form phases such as Al3Fe, and the strength and hardness of the aluminum alloy are improved, so that the balance between the mechanical properties and the electrical conductivity of the motor rotor casting aluminum alloy is achieved.

The invention relates to the field of valve bodies, in particular to a machining process of a stop valve body, which comprises the following steps: annealing, stably putting the valve body into an annealing furnace, setting the temperature of the annealing furnace at 680-750 DEG C, keeping for 1-2 hours to ensure that the temperature is uniform, slowly cooling in the furnace or slowly cooling in slag outside the furnace, taking out the valve body after cooling, and detecting the quality of the valve body. The valve body is placed in a heating furnace, the valve body is heated to 850-950 DEG C, heated to the critical temperature interval of steel and heated to the target temperature, the temperature is kept for 15-30 min, then the valve body is taken out of the furnace and naturally cooled to the room temperature, the internal stress of the material is eliminated through annealing, and the material is prevented from deforming or cracking in subsequent machining; and the annealed material has good plasticity and toughness, subsequent secondary machining is facilitated, the strength and hardness of the material can be remarkably improved through normalizing, the mechanical performance of the material is improved, the strength and hardness of the obtained material are higher, and the normalized valve body material is more uniform in grain and more refined in structure.

The invention discloses a preparation method and application of epoxy resin-glass fiber cloth-melamine compound-aluminum diethylphosphinate blended epoxy resin with high flame retardance and high toughness, and relates to the technical field of polymer composite materials. The invention aims to solve the problem that the traditional composite epoxy resin material cannot have high flame retardance and high toughness at the same time. The epoxy resin-glass fiber cloth-melamine compound-aluminum diethylphosphinate blended epoxy resin prepared by the preparation method disclosed by the invention keeps stable performance in a high-temperature and severe environment, and has good weather resistance, chemical corrosion resistance and dimensional stability. Modification is performed through an environment-friendly halogen-free flame-retardant system, and the adopted melamine compound and aluminum diethylphosphinate are both halogen-free environment-friendly flame retardants, so that release of toxic gas in the combustion process can be effectively reduced. The invention can obtain the preparation method and the application of the epoxy resin-glass fiber cloth-melamine compound-aluminum diethyl phosphinate blended epoxy resin with high flame retardance and high toughness.

The invention discloses a low-density flexible environment-friendly moisture-proof thermal insulation composite material as well as a preparation method and application thereof, and belongs to the technical field of thermal protection composite materials and preparation thereof. The problem that an existing heat preservation and insulation material is poor in flexibility and heat insulation performance is solved. Natural fibrilia is pretreated to improve the flexibility and reaction activity of the natural fibrilia, and then the natural fibrilia is compounded with flexible polysiloxane aerogel through a sol-gel and normal-pressure drying method, so that the aerogel composite material with low density, high flexibility and good heat preservation and heat insulation properties is obtained. The prepared low-density flexible environment-friendly moisture-proof heat preservation and heat insulation composite material has the advantages of being excellent in flexibility and heat insulation performance, easy to fold, unfold and deform, large in failure strain, insensitive to damage and good in adaptability to surrounding structures, and the problems that an existing heat preservation and heat insulation material is large in brittleness and poor in adaptability to the surrounding structures are solved.

This invention provides a diamond composite coated drill bit and its preparation method, comprising a bonding layer, a diamond grinding layer, and a reinforcing layer. The bonding layer is directly deposited on the surface of the drill bit substrate and formed by magnetron sputtering. The bonding layer is a composite phase of tungsten carbide and chromium. The diamond grinding layer is deposited on the surface of the bonding layer and formed by chemical vapor deposition. The diamond grinding layer consists of a composite structure of micron-sized diamond framework and nano-sized diamond filler layer. The reinforcing layer is deposited on the surface of the diamond grinding layer and formed by magnetron sputtering of a molybdenum and boron composite cermet layer. This invention is applicable to PCB board processing, extending the service life of drill bits and improving processing efficiency.

The application relates to a zirconia / silicon carbide / silicon oxide nanofiber and a preparation method and application thereof. The method comprises the following steps: adding a liquid silicon source into a zirconium sol solution, stirring uniformly to obtain a spinning solution; performing electrostatic spinning on the spinning solution, drying to obtain a nanofiber precursor; performing oxygen-free sintering to obtain the zirconia / silicon carbide nanofiber; wherein the zirconia serves as a fiber center; a silicon carbide layer is coated outside the zirconia; heat treatment is performed to oxidize the silicon carbide layer close to the outer surface to obtain the zirconia / silicon carbide / silicon oxide nanofiber. The technical problem to be solved is how to provide the zirconia / silicon carbide / silicon oxide nanofiber, so that the nanofiber has high elasticity, high flexibility, low density, low thermal conductivity, strong comprehensive performance and greatly expands the popularization and application of the zirconia fiber.

The invention discloses a tungsten-molybdenum-tantalum-niobium alloy powder material and a preparation method thereof, and belongs to the technical field of composite alloy material preparation, the tungsten-molybdenum-tantalum-niobium alloy powder material comprises the following raw materials by mass: 55-60 parts of tungsten powder, 20-30 parts of molybdenum powder, 15-25 parts of tantalum powder, 5-10 parts of niobium powder, 1-3 parts of a compound, and 0.2-0.4 part of a reinforcing filler. The tungsten disulfide nanotube is synthesized on the surface of the carbon fiber, and the cavity structure of the tungsten disulfide nanotube is filled with the carbon fiber, so that the situation that pores exist when the tungsten disulfide nanotube is added into alloy powder, and consequently the mechanical property of the alloy is reduced is avoided; in the sintering process, palm leaf cellulose generates a carbon element which reacts with metal elements in the tungsten-molybdenum-tantalum-niobium alloy to form metal carbide, the metal carbide serves as a strengthening phase of the alloy, the composite strengthening effect of solid solution strengthening and dispersion strengthening is achieved, and the tensile strength and the yield strength of the alloy are improved.