79results about How to "Play a role in strengthening and toughening" patented technology

The invention discloses a high strength and toughness 3Y-TZP composite ceramic and a preparation method thereof. The 3Y-TZP composite ceramic consists of 3Y-TZP, a SiC crystal whisker and Sr2Nb2O7; and the preparation method of the 3Y-TZP composite ceramic comprises the steps of preparing and mixing Sr2Nb2O7 powder, ball milling, profiling, degumming and sintering. The composite ceramic is obtained by sintering the SiC crystal whisker and a Sr2Nb2O7 ferroelectric material second-phase addictive which are introduced into the 3Y-TZP. The ceramic material with high strength and toughness can be obtained by adjusting the contents of the SiC crystal whisker and the Sr2Nb2O7 and optimizing a microwave sintering process under the synergistic effect of reinforcing by the SiC crystal whisker and toughening by the Sr2Nb2O7 piezoelectric second phase. The invention has reasonable components and simple preparation process and simultaneously achieves the effects of strengthening and toughening by adopting a synergistic technology of reinforcing by the SiC crystal whisker and toughening by the Sr2Nb2O7 piezoelectric second phase. In addition, the invention is applicable for industrial production, effectively improves the mechanical property of the 3Y-TZP ceramic and widens the application field of the 3Y-TZP ceramic.

The invention discloses a SiC nanowire in-situ enhanced SiCf/SiC composite material and a preparation method of the SiC nanowire in-situ enhanced SiCf/SiC composite material. The composite material is prepared from a SiC fiber prefabricated part, SiC nanowires and a SiC ceramic matrix, wherein the SiC nanowires grow on a fiber surface of the SiC fiber prefabricated part in situ; the SiC nanowires are mutually wound to form a net-shaped structure; the SiC ceramic matrix is arranged in a pore of the SiC fiber prefabricated part. The preparation method comprises the following steps: (1) carrying out surface chemical modification treatment; (2) loading a catalyst; (3) carrying out chemical vapor deposition; (4) impregnating a precursor and cracking. The SiC nanowire in-situ enhanced SiCf/SiC composite material provided by the invention has the advantages that the SiC nanowires are uniformly distributed and are combined with SiC fibers well, the toughness is good and the density is high and the like; the preparation method is simple in process, low in requirements on equipment, environmental-friendly, and good in process commonality; the introduction volume fraction of the SiC nanowires is high and is controllable.

The invention discloses epoxy resin tow prepreg. A system of resin with high toughness and fatigue resistance is adopted, and an added reinforcing agent improves the strength and toughness of a material from the perspective of omnidirectional mechanics; and the obtained tow prepreg is excellent in mechanical property, high in strength, good in toughness and high in fatigue resistance. The invention further discloses a composite material high-pressure hydrogen storage tank. A graphene modified inner container is adopted, the mechanical properties and the toughness of the hydrogen storage tank are improved in combination with the epoxy resin tow prepreg with excellent performance and a thermoplastic resin tow prepreg winding layer, the hydrogen storage tank is suitable for the storage and use environment of high-pressure hydrogen and liquid gas, the fatigue resistance is good, and the service life is long. The invention further discloses a preparation process of the composite material high-pressure hydrogen storage tank. The preparation of prepreg by wet process and hot melt can be realized, an inner container self-tightening process and a winding process can generate a higher innercontainer self-tightening effect and enable tension of each fiber bundle to be more uniform, the strength advantage of fibers is fully utilized, and the fatigue resistance is good.

The invention provides high-strength bolt steel with excellent delayed fracture resistance and a preparation method thereof. The high-strength bolt steel comprises the following components in percentage by weight: 0.35-0.50% of carbon, 0.20-0.70% of manganese, 0.75-1.35% of chromium, 0.55-1.45% of molybdenum, 0.10-0.50% of vanadium, 0.005-0.10% of aluminum, 0-0.005% of sulfur, 0.02-0.05% of silicon, 0.005-0.15% of titanium, 0.0005-0.003% of oxygen, 0.001-0.007% of nitrogen, and the balance iron and other inevitable impurities; the content of titanium is not less than 3.5 times of the content of nitrogen; the sum of the contents of chromium, molybdenum and vanadium is not lower than 1.75%; and the sum of the contents of sulfur, oxygen and nitrogen is not higher than 0.01%. The high-strength bolt steel is high in purity and refined in grains, can be used for manufacturing high-strength bolts with tensile strength not lower than 1400MPa, has a section shrinkage rate not lower than 50%, is excellent in delayed fracture resistance, and can be applied to automobiles and mechanical parts.

The invention discloses a calcium-carbonate-supported nucleating agent used for poly(lactic acid) crystallization and a preparation method thereof. The nucleating agent comprises the following composition formula: calcium carbonate and phenylphosphonic acid at a weight ratio of (5-40): 1, wherein calcium phenylphosphate generated by reaction of phenylphosphonic acid and calcium carbonate is used as an active ingredient and loaded on the surface of calcium carbonate, and phenyl phosphonic acid has a structural formula shown in the invention, in the formula, R1 and R2, the same or different, represent hydrogen atom, C1-10 alkyl or C1-10 alkoxycarbonyl. The nucleating agent can increase the effective nucleation sites formed by the high-degree dispersion of calcium phenylphosphate on the surface of calcium carbonate, thereby increasing nucleation efficiency as well as strengthening and toughening poly(lactic acid), avoiding the problem that poly(lactic acid) has poor toughness caused by non-supported nucleating agents, and facilitating the wide application of poly(lactic acid). The nucleating agent has a simple preparation method, low consumption of phenylphosphonic acid and significantly low cost.

The invention relates to a polymer coarse fibre used for concrete and a preparation method. The polymer coarse fibre is cylindrical, and the surface of the coarse fibre is provided with more than one anchored sheet distributed along the axial direction. The preparation method comprises the following steps: after polymer is dried to constant weight, adding the polymer to a twin-screw extruder; after the polymer is extruded by a spinneret plate hole, cooling a strand; then, stretching by stages for times at the temperature higher than the polymer vitrification temperature; after stretching is finished, cutting the anchored sheet on the surface of the strand; then, carrying out heat setting; and finally cutting off and packaging to obtain the polymer coarse fibre. In the preparation method, the appearance shape of the fibre is changed, so that the coarse fibre and a matrix have good interfacial bonding force, and therefore the cracking resistance, bending resistance, toughness and impact resistance of the coarse fibre enhanced concrete are enhanced or improved.

The invention relates to a poly-hydroxyalkanoate degradable composite material containing a carbon nanomaterial and a preparation method thereof. The composite material is constructured by introducing a high thermal conductive carbon nanomaterial into a poly-hydroxyalkanoate matrix to form an efficient thermal conductive network in the composite material to accelerate dissipation of heat discharged by crystals. The carbon nanomaterial is used as a nucleating agent at the same time to promote nucleation and crystallization of the poly-hydroxyalkanoate matrix. The carbon nanomaterial is further used as a flexibilizer to strengthen the obtained composite material. The mass ratio of the poly-hydroxyalkanoate matrix to the carbon nanomaterial is 10:1 to 2000:1. Compared with the prior art, the carbon nanomaterial has the advantages of high machining property, high mechanical property and high thermal property, low production cost and the like.

The invention provides a graphene epoxy compound material for an electric automobile driving module and a preparation method. The compound material disclosed by the invention is formed by compoundinggraphene/inorganic powder particle hybrid materials with epoxy resin; the graphene/inorganic powder particle hybrid materials as filler are uniformly dispersed into a basal body of the epoxy resin. Byadopting the graphene/inorganic powder particle hybrid materials as the epoxy resin filler, the advantages of excellent performance such as high graphene strength and good heat conduction performanceof graphene as well as high heat conductivity, low expansion coefficient, high filling property, low stress and the like of inorganic powder particles can be fully developed, the defect of easiness for aggregation of the graphene/inorganic powder particle hybrid materials and the epoxy resin is overcome, enhancement and toughening effects can be achieved, and the application performance of the resin is improved. The compound material prepared by adopting the technical scheme has the special performance such as high heat conductivity, high adhesion strength, small change of curing volume, strong weathering resistance, high temperature resistance, small heat expansion coefficients and the like, and is very suitable for being used as an epoxy material for encapsulation in an overall encapsulation technology of a new-energy automobile motor driving module.

The invention discloses a flame-retardant PBT/PA alloy material and a preparation method thereof. The alloy material comprises the following raw materials in parts by mass: 30-42 parts of a PBT resin, 8-15 parts of a transparent PA resin, 6-12 parts of a glow wire temperature increasing agent, 7-12 parts of brominated polystyrene, 2-5 parts of antimonide, 20-35 parts of glass fibers, 3-5 parts of a compatilizer, 0.1-1 part of an antioxidant and 0.1-1 part of a lubricating agent. The PBT/PA alloy material disclosed by the invention is enhanced by the glass fibers and is excellent in mechanical property, a novel glow wire temperature increasing agent is adopted, the material can reach the level V0, high glow wire temperature and high CTI of the material can be obtained, and the alloy material can be used for preparing contactors and circuit breakers.

The invention provides a boron carbide ceramic plate which is formed by splicing ceramic chips. Graphene highly dispersed in the ceramic chips has excellent electroconductive, heat-conducting and mechanical performance and is a two-dimensional material, so that mutual attraction among graphene layers can be remarkably lowered through surface modification to avoid aggregation; graphene has high dispersity and stability in some liquid media, so that a graphene solution stable in dispersion can be prepared; a graphene-ceramic mixed raw material having good implanting effect can be obtained by mixing graphene with ceramic matrix size; graphene plays a role in strengthening and toughening through mechanisms of ceramic interface pinning, crack deflection inducing, bifurcating and crack bridging,graphene breaking and extracting and energy absorbing.

The invention relates to a niobium-aluminum alloying molybdenum disilicide material and a preparation method thereof, and belongs to the technical field of intermetallic compounds. The chemical formula of the niobium-aluminum alloying molybdenum disilicide material is (Mo1-xNbx)(Si1-yAly)2, wherein X ranges from 0 to 0.15, and Y ranges from 0 to 0.15. The preparation method comprises the following steps of: uniformly mixing molybdenum, niobium, silicon and aluminum powder at a mole ratio of (28.305-33.3):(0-4.995):(56.695-66.7):(0-10.005); then pressing the mixture into a blank; and placing the blank into a combustion synthesis device, and igniting the blank in a protective atmosphere to synthesize the niobium-aluminum alloying molybdenum disilicide material. Compared with the prior art, the niobium-aluminum alloying molybdenum disilicide material disclosed by the invention can be synthesized through a one-step method and has the advantages of good high-temperature strength, simple process and equipment, time and energy conservation, low cost and less pollution.