3012 results about "Plastic property" patented technology

The invention relates to a hot-rolled wire rod for a 2060MPa-grade stranded wire and a manufacturing method of the hot-rolled wire rod. Mn-Cr high-carbon chemical component design and rolling spinning are performed to form a wire rod, then online molten salt isothermal phase change treatment is performed, the wire rod is firstly subjected to front-section molten salt treatment and enters a sorbite phase region from an austenite state to form a structure taking a sorbite structure as a main structure, and then the wire rod is subjected to rear-section molten salt treatment, so that the hot-rolled wire rod is obtained. The method comprises the following steps of: firstly, carrying out heat treatment on the residual austenite, promoting the unconverted residual austenite to be converted into a sorbite structure, simultaneously promoting isothermal tempering of the structure and fusing of a part of sorbite lamellas, and finally, slowly cooling through a roller way to prepare a hot-rolled wire rod of which a microscopic structure comprises a mixed structure consisting of tempered sorbite, tempered ferrite and fused sorbite, so that the material cost can be controlled; the high-strength and high-plasticity performance matching of the wire rod is improved, the tensile strength is 1370-1420 MPa, the percentage reduction of area is 35%-40%, and the mechanical property fluctuation is reduced, so that the wire breaking risk in stranded wire production is reduced, and efficient and stable production is promoted.

The invention discloses preheating-free welding maritime work steel with excellent low-temperature toughness and a preparation method of the preheating-free welding maritime work steel, and belongs to the field of steel and iron material preparation. The produced steel plate has good comprehensive mechanical properties through alloy component-secondary rolling-controlled cooling process coupling design, the problem that the strength, plasticity, low-temperature toughness and preheating-free post-welding performance of the steel plate are difficult to match and harmonize is solved, the steel plate has ultrahigh-strength plasticity, excellent low-temperature toughness and excellent Z-direction performance, and room-temperature preheating-free welding can be achieved.

The invention discloses a forging method for improving plasticity of a large invar alloy steel ingot and invar alloy, and the forging method comprises the following steps: smelting molten steel by adopting an electric furnace, and casting to obtain the large invar alloy steel ingot with the weight of 15-25t; the cold-state invar alloy steel ingot is heated to 1000-1200 DEG C for heat preservation, and the heat preservation time is controlled to be longer than or equal to 10 h; the heated invar alloy steel ingot is subjected to three-heating-number upsetting and drawing-out, upsetting is conducted according to the rolling reduction of 15-50% of the total height of the invar alloy steel ingot in each heating number, the invar alloy steel ingot is drawn out to the height of the original invar alloy steel ingot after upsetting, and the invar alloy steel ingot is returned to a heating furnace to be heated and subjected to heat preservation after upsetting and drawing-out in each heating number; the final forging temperature of the last heating number is greater than or equal to 750 DEG C; and the invar alloy steel ingot subjected to heating and heat preservation in the last heating number is forged to the specified size, and then the invar alloy steel ingot is slowly cooled to the room temperature in air to obtain an invar alloy steel forging stock. The thermoplasticity of the large invar alloy steel ingot is improved, and the technical problem that the large invar alloy steel ingot is prone to cracking during forging is solved.

The invention relates to a hot-rolled wire rod for a 2100MPa-grade stranded wire and a manufacturing method thereof, after a high-carbon and high-silicon component system is rolled and spun into a wire rod, the wire rod is cooled at a cooling speed of more than or equal to 31 DEG C / s through online molten salt sorbite regulation and control treatment, and enters a sorbite phase region from an austenite state; the method comprises the following steps of: forming a structure mainly comprising a sorbite structure, performing isothermal tempering, promoting fusing of a part of sorbite lamellas, and finally performing roller way cover opening and slow cooling to prepare the hot-rolled wire rod of which the microscopic structure comprises a mixed structure consisting of tempered sorbite, tempered ferrite and fused sorbite, so that alloy components can be simplified, and the strong plasticity matching and the structure uniformity of the wire rod can be improved; the tensile strength is 1420-1470 MPa, the percentage reduction of area is 36%-41%, the composite material is used for the application field of manufacturing 2100 MPa grade stranded wires and the like, off-line heat treatment can be avoided, and the risk of wire breakage during downstream drawing and twisting is reduced.

This invention discloses a stainless steel welding wire for repair welding of martensitic stainless steel turbine runners, its preparation method, and its application, belonging to the field of metal welding material preparation technology. The chemical composition of the welding wire provided by this invention, expressed as a percentage by weight, is: C≤0.03%, Si: 0%~0.6%, Mn: 5.0%~8.0%, S≤0.010%, P≤0.020%, Cr: 12.5%~15.5%, Ni: 5.0%~7.0%, Mo: 1.0%~2.0%, with the balance being Fe and impurities. The welding wire provided by this invention is suitable for repair welding of Cr13Ni4~6 type martensitic stainless steel, and post-weld heat treatment is not required. The weld metal produced by this welding wire exhibits good strength, plasticity, and toughness, with a tensile strength ≥750MPa, elongation after fracture ≥35%, and impact absorption energy at -40℃ ≥120J.

The invention relates to the technical field of metal plastic forming, and discloses a titanium alloy radial forging reduction rate collaborative optimization method based on material testing, which comprises the following steps of: acquiring dynamic characteristic data in a forging process in real time by acquiring multi-dimensional material performance parameters, and constructing a multi-target collaborative optimization model; and intelligent collaborative configuration of the reduction rate parameters is realized by adopting a self-adaptive weight distribution strategy. And a thermal coupling factor normalization equation and a phase field free energy functional normalization model are established, and the technical problems that in a traditional forging process, due to empirical configuration of reduction rate parameters, the structure is uneven, and residual stress exceeds the standard are solved. A lightweight model is deployed through edge computing nodes, millisecond-level dynamic correction of an optimization scheme is realized in combination with a 5G industrial private network, and the grain size qualification rate and the size precision of the titanium alloy forgings are improved. The method improves the yield of the grain size of the forge piece, ensures that the residual stress of the forge piece is reduced, stably controls the size precision, and improves the batch stability of high-end titanium alloy parts.

The invention provides a 10.9-grade non-quenched and tempered cold heading steel wire rod and a production method thereof. The 10.9-grade non-quenched and tempered cold heading steel wire rod comprises the following chemical components: 0.23-0.27% of C, 0.30-0.50% of Si, 1.45-1.55% of Mn, less than or equal to 0.025% of P, less than or equal to 0.025% of S, 0.40-0.50% of Cr, 0.025-0.050% of Ti, 0.0025-0.0050% of B, less than or equal to 0.0050% of N and more than or equal to 0.015% of [Ti]-3.5 * [N]. According to the invention, on the basis of component design, a controlled rolling process deformation induced phase change, an online salt bath isothermal treatment cooling process and an artificial aging process are matched, so that rapid cooling and isothermal phase change of the wire rod are realized, and the prepared wire rod is uniform in through ring mechanical property, high in yield ratio, good in plasticity and long in fatigue life. The steel wire rod can be used for directly cold-drawing the steel wire without annealing, and the cold-drawn steel wire can meet the performance requirement of a 10.9-grade fastener without quenching and tempering after being formed. According to the production method of the wire rod, the production process can be simplified, the fastener production period is shortened, the cost is reduced, meanwhile, the energy consumption is reduced, and the method conforms to the current green and low-carbon development route.

The present application relates to the technical field of metal plastic forming, and discloses a titanium alloy radial forging reduction rate collaborative optimization method based on material testing, which acquires dynamic characteristic data of a forging process in real time through multi-dimensional material performance parameter collection, constructs a multi-objective collaborative optimization model, and realizes intelligent collaborative configuration of the reduction rate parameter by using an adaptive weight distribution strategy. A thermal coupling factor normalization equation and a phase field free energy functional normalization model are established to solve the technical problems of uneven structure and excessive residual stress caused by the empirical configuration of the reduction rate parameter in the traditional forging process. A lightweight model is deployed through an edge computing node, and millisecond-level dynamic correction of the optimization scheme is realized in combination with a 5G industrial private network, thereby improving the grain size qualification rate and size accuracy of titanium alloy forgings. The present application improves the grain size qualification rate of forgings, ensures stable control of the size accuracy while reducing the residual stress of forgings, and improves the batch stability of high-end titanium alloy components.

The invention belongs to the technical field of metal composite materials and hydrogen storage and transportation materials, and particularly relates to a high-strength hydrogen-embrittlement-resistant layered metal composite material for hydrogen storage and a preparation method and application of the high-strength hydrogen-embrittlement-resistant layered metal composite material. According to the preparation method, the nickel-saving austenitic stainless steel (NEASS) and the 30CrMo steel are alternately overlapped in a multi-layer mode, and the processes of vacuum electron beam welding, high-temperature hot rolling, accumulative ply rolling, multi-stage heat treatment and the like are combined, so that the composite board with the layer number reaching hundreds of layers, firm interface bonding, excellent mechanical performance and good hydrogen embrittlement resistance is prepared; the technical problem that strength, toughness and hydrogen brittleness resistance of an existing metal material in a high-pressure hydrogen environment are difficult to consider at the same time is solved. The obtained composite material has high strength, high plasticity and excellent hydrogen embrittlement resistance, and is suitable for structural materials of high-pressure hydrogen storage tanks, hydrogen conveying pipelines and other key hydrogen energy equipment.

The application discloses a preparation method of high-strength and high-plasticity additive manufacturing nickel-based high-temperature alloy. The application effectively solves the problem of high strength and low plasticity of the nickel-based high-temperature alloy caused by heat treatment of precipitation strengthening, and obtains high-performance nickel-based high-temperature alloy with a tensile strength of 1609 MPa and an elongation rate of 16.6%. The application first uses 1160 DEG C. to 1200 DEG C. solid solution treatment, and then carries out 843 DEG C. / 4 h+760 DEG C. / 8 h two-stage aging heat treatment process, to prepare a multi-scale heterogeneous structure composed of bimodal size distribution grains, nano second phases and nano defects, and the heat-treated product has excellent strength and plasticity. The preparation process is simple, controllable and adjustable, the product has excellent performance, and is convenient for large-scale industrial application.

The invention discloses multi-source composite expansion super-early-strength concrete and a preparation method thereof. The concrete comprises a cementing material, aggregate, a water reducing agent, water and a multi-source composite expansion system. The expansion system is composed of a plastic expansion agent, a calcium sulphoaluminate early expansion source, a magnesium oxide delayed expansion source and an internal curing material. Through precise component design and function time sequence matching, a cooperative compensation network covering the whole life cycle of the concrete is constructed, a plastic expanding agent inhibits plastic shrinkage, calcium sulphoaluminate compensates early-stage self-shrinkage, magnesium oxide resists medium-and-long-term drying shrinkage, an internal curing material provides continuous moisture guarantee for the above process, and the overall performance of the concrete is improved. And the efficiency of each expansion source is excited and coupled. According to the invention, seamless and accurate shrinkage compensation from a plastic stage to a service later stage can be realized on the premise of ensuring the super early strength characteristic of the concrete, the technical problem that the super early strength concrete is easy to crack due to severe shrinkage is fundamentally solved, and the volume stability and durability of the structure are remarkably improved.

The invention discloses a brazing method for improving the welding strength of a polycrystalline diamond cutter and a hard alloy. The brazing method comprises the following steps that S1, brazing filler metal alloying is conducted; and S2, the PCD tool bit and the hard alloy matrix are subjected to vacuum brazing. According to the brazing filler metal, an Ag-Cu-Co system is adopted, Ag mainly plays a role of a solder matrix and provides plasticity and thermal conductivity, Cu mainly plays a role of forming an eutectic structure with Ag and reducing the melting point, and Co mainly plays a role of wetting the surfaces of PCD and hard alloy. Co infiltration is adopted in the preparation process of the PCD tool bit used in the method, so that a certain amount of Co exists on the PCD surface, and the hard alloy tool body also contains Co, and therefore, a small amount of Co in the brazing filler metal can better wet the welding surface according to the similar intermiscible principle. In the vacuum brazing process, additional pressure does not need to be applied, when the brazing filler metal is molten, the brazing filler metal is evenly laid on the welding face under the action of the pressure of the PCD tool bit on the upper portion and the capillary effect, the redundant brazing filler metal can flow out of the two sides of the mold, and the flatness of the welding surface can be effectively guaranteed.

The invention discloses a finite element simulation method for evaluating the reliability of a battery structure, a product and a storage medium. The method comprises the following steps: constructing a battery finite element model comprising a shell and a sealing structure; defining elastoplastic material properties for the shell; applying a pressure load for simulating internal gas production and / or a mechanical load for simulating external impact; after solving, extracting a plastic strain result of the sealing structure area; and evaluating the integrity of the sealing function based on the result. According to the method, the elastic-plastic model is adopted, the limitation that a calculation result is distorted after a material is yielded in traditional linear simulation is overcome, and the plastic failure risk can be accurately predicted; meanwhile, a sealing function failure criterion based on plastic strain is innovatively established, and the problem that sealing performance evaluation of key connection structures such as riveting cannot be achieved is solved. According to the method, a systematic and quantitative safety boundary defining tool is provided for the battery structure design, and the reliability and efficiency of the design are remarkably improved.

The invention relates to the field of metal plastic forming control, and discloses a self-adaptive control system and method for forging and pressing aviation precision forgings, and the system comprises an online dynamic model identification module which identifies a process fingerprint representing the characteristics of a current blank at the initial stage of machining; the target curve self-adaptive regulator is used for regulating a reference energy dissipation rate curve according to the fingerprint and generating a personalized reference curve; the model prediction controller performs rolling optimization by using continuously updated model parameters and taking the reference curve as a tracking target, and outputs an optimal speed instruction; and the event triggering and constraint dynamic modulation module is used for actively tightening the operation constraint applied to the controller before a forging pressure sudden increase event is pre-judged through a parallel monitoring model prediction error. According to the method, through combination of target self-adaption and constraint dynamic modulation, control over the forging and pressing process is achieved, forging pressure overshoot can be effectively restrained, and the forming precision and batch-to-batch quality consistency of forge pieces are remarkably improved.

The invention relates to the technical field of additive manufacturing, in particular to a direct aging treatment process of an SLM molded Ti-6Al-4V alloy and a product thereof, and the direct aging treatment process comprises the following steps: firstly, manufacturing a Ti-6Al-4V alloy sample by adopting an SLM technology, and then putting the SLM molded Ti-6Al-4V alloy sample into a vacuum heat treatment furnace for direct aging treatment, and finally, taking out the sample after furnace cooling or air cooling. According to the method, through direct aging treatment, a natural alpha'martensite structure in the Ti-6Al-4V alloy formed through SLM is decomposed into an alpha + beta double-phase structure, the front solid solution-quenching process in traditional solid solution aging treatment is not needed, and the purposes of optimizing structure uniformity and improving plasticity are achieved. The aging treatment cost and the quenching risk of the SLM titanium alloy are reduced, and the plasticity of the SLM titanium alloy can be remarkably improved while high strength is kept. The method is simple in process, low in cost and suitable for large-scale industrial application.

The invention relates to 500MPa-grade preheating-free welding structural steel and a preparation method thereof, belongs to the technical field of structural steel, and solves the problems that in the prior art, traditional structural steel is poor in welding performance, high in carbon equivalent, high in cold crack sensitivity and difficult to consider both high strength and good plasticity. The structural steel comprises the following chemical components in percentage by weight: less than 0.002% of C, less than 0.02% of Si, less than 0.03% of Mn, 1.5-2.0% of Ni, 1.5-2.0% of Cu, less than 0.0008% of S, less than 0.006% of P and the balance of Fe and inevitable impurities, wherein the carbon equivalent Ceq is less than or equal to 0.27. The combination of high strength (the yield strength is larger than or equal to 550 MPa, and the tensile strength is larger than or equal to 650 MPa), excellent welding performance (Pcm is smaller than or equal to 0.14), good plasticity (the percentage elongation after fracture is larger than or equal to 25%, and excellent low-temperature toughness (the impact energy at the temperature of-20 DEG C is larger than or equal to 200 J) is achieved, and the steel is suitable for the structural fields of ships, bridges, buildings and the like with strict requirements for welding performance and mechanical performance.

The invention discloses a test-based crystal plasticity and cohesion model coupling hydrogen induced cracking simulation method, which comprises the following steps: carrying out a hydrogen filling mechanical property test on a metal material to obtain a true stress-true strain curve of the metal material in a hydrogen environment; carrying out a hydrogen-filled fracture toughness test on the metal material to obtain a stress intensity factor of the metal material in a hydrogen environment; constructing a cohesion constitutive model; a metal material electron back scattering diffraction microscopic characterization test is carried out, microstructure characteristics are obtained, and a polycrystalline model is constructed; constructing a crystal plastic constitutive model; coupling crystal plasticity constitutive and cohesion constitutive, and calibrating crystal plasticity to-be-determined parameters by adopting a trial-and-error method; and carrying out finite element simulation analysis on hydrogen-induced cracking behaviors with different microstructure characteristics in a hydrogen environment to obtain stress-strain data and crack data of the hydrogen-induced cracking behaviors. According to the invention, high-precision simulation of the hydrogen-induced cracking micromechanism of the metal material in the hydrogen environment is realized.

The invention provides a Fe-containing Ti-Al-Mo series high-strength, high-plasticity and low-cost titanium alloy. The titanium alloy comprises the following components in percentage by mass: 6.0%-7.5% of Al, 0.5%-2.5% of Fe, 1.0%-2.5% of Mo, 0.5%-2.0% of V, 1.5%-3.5% of Zr and 0%-2.0% of Sn. And the balance of Ti and inevitable impurities. The microscopic structure of the titanium alloy is a first tissue structure or a second tissue structure, the first tissue structure comprises an equiaxed primary alpha phase and a secondary alpha phase, and the second tissue structure comprises an equiaxed primary alpha phase, a lamellar primary alpha phase and a secondary alpha phase; wherein the equiaxial primary alpha phase is uniformly distributed in the beta matrix, the lamellar primary alpha phase is distributed in the beta matrix along the deformation direction, and the secondary alpha phase is uniformly dispersed and distributed in the beta matrix. A performance foundation is laid through component design and element matching, directional regulation and control of an alloy microstructure are achieved by combining precise forging and heat treatment processes, excellent matching of high strength and high plasticity is finally obtained, and meanwhile the production cost is remarkably reduced.

The invention belongs to the field of advanced metal plastic processing, and particularly relates to a difficult-to-deform metal ultra-thin strip rolling device and method.The device comprises an uncoiler, a high-strength rolling mill and a coiler which are sequentially arranged, and the inlet side and the outlet side of the high-strength rolling mill are each provided with a pair of equal-diameter rollers; the equal-diameter roller is composed of a copper conductive roller and a ceramic insulating roller, the copper conductive roller on the inlet side and the copper conductive roller on the outlet side are electrically connected to the positive electrode and the negative electrode of the pulse power source respectively, and a strip blank on the uncoiling machine sequentially penetrates through the equal-diameter roller on the inlet side, the high-strength rolling mill and the equal-diameter roller on the outlet side and then is wound on the coiling machine. And a working roll, which is in contact with the strip blank, on the high-strength rolling mill is an insulating ceramic working roll. The pulse current in the method can induce dynamic recrystallization, an ultra-fine grain or nanocrystalline structure is obtained, and the strength and plasticity matching of the product is superior to those of a traditional process. Meanwhile, long-time high-temperature oxidation can be avoided by adopting pulse current to heat the strip blank, and the surface is bright.

The invention discloses a grouting and filling method for a cross-layer area of a coal pillar group in a residual mining area, and relates to the technical field of coal mining, which comprises the following steps of: (1) selecting a key layer; (2) a drill hole is constructed in the key layer, a directional initial crack is formed in the drill hole through frosted water jet cutting, then the two ends of the drill hole are set, and the initial crack is expanded to form a crack network in the mode that high-pressure fluid is injected into a hole sealing section; (3) grouting materials are adopted for conducting segmented grouting construction on the drill holes in the step (2), specifically, firstly, low-viscosity grout is used for filling a crack network formed through fracturing, then medium-viscosity grout is used for filling a coal pillar plastic area influenced by mining, and finally high-viscosity grout added with an accelerating agent is used for filling roof fractured rock mass and goaf and goaf roadways; and (4) after the slurry is solidified, a coal pillar-slurry vein body-overlying strata composite bearing structure is formed. According to the invention, the rock mass cohesive force and overall strength of the re-mining area can be obviously enhanced, and the stability of re-mining roadways and working face surrounding rocks is improved.

The invention discloses a microdefect-containing high-temperature structure damage regulation and control method based on a dual-scale modeling method and a related device, and relates to the technical field of structural integrity evaluation and optimization of high-temperature alloy materials, and the method comprises the following steps: obtaining a plurality of alloy experiment samples subjected to standard heat treatment; the method comprises the following steps: establishing a macroscopic-microscopic dual-scale model based on an alloy experimental sample; mapping the macroscopic displacement field to a microscopic model in the macroscopic-microscopic dual-scale model, calculating a local plastic slippage cumulant, and taking a cumulative plastic slippage critical value as a fatigue failure criterion; based on the local plastic slippage cumulant and the cumulative plastic slippage critical value, defect parameter sensitivity evaluation is conducted on the alloy experiment sample, and the influence of the defect shape, the defect size and the defect position on the fatigue life is obtained; and carrying out surface gradient microstructure strengthening on the high-sensitivity area, optimizing a defect form through plastic deformation and transferring a damage accumulation position. The service life of the high-temperature structural part is remarkably prolonged.

The invention belongs to the technical field of high-temperature alloy production, and relates to a large-size GH4141 high-temperature alloy fine-grain bar and a preparation method thereof.By means of the forging technology of high-temperature cogging forging, low-temperature forging and medium-temperature finished product forging, the plasticity of a cast ingot is improved through upsetting and drawing-out in the high-temperature stage, and an as-cast structure is fully broken; grains are refined through low-temperature stage upsetting and drawing deformation, and distortion energy is accumulated; through the synergistic effect of dynamic recrystallization and static recrystallization, the bar structure is further refined, and the structure uniformity is improved.

The invention relates to the technical field of metal material manufacturing, and discloses a manufacturing process of a super-strong wear-resistant tire protection chain, which comprises the following steps of: forming a chain link blank by adopting high-silicon high-manganese bainite steel through hot rolling and hot die forging; the core of the method is an integrated heat treatment step, specifically, surface functionalization co-permeation of copper and cerium elements is synchronously carried out in the austenitizing stage, then bainite isothermal quenching is carried out, and a composite structure of bainite and stable retained austenite is obtained in a matrix; the process further comprises the steps that a special high-toughness welding wire is adopted for welding, and local tempering treatment is conducted on a welding seam; by means of the scheme, the chain link is endowed with excellent obdurability and fatigue resistance through the phase transformation induced plasticity effect of the base body, the abrasion resistance is remarkably improved through the surface functionalization co-cementation layer, and the reliability of a joint area is ensured through accurate welding and postweld treatment. The technical problems that wear resistance and toughness of a traditional protection chain are difficult to consider at the same time, and a welding joint is prone to failure are systematically solved.

The invention discloses a welding thermal stress simulation method, device, equipment and medium based on a crystal plasticity finite element, and relates to the technical field of welding thermal stress finite element simulation. The method comprises the steps that a sample is prepared according to a specific multi-phase metal material, and phase distribution and crystal orientation information of a two-dimensional plane of the material are obtained through a metallographic experiment; and a three-dimensional multi-grain model is constructed based on the two-dimensional information. According to the method, a crystal plastic constitutive model is adopted to describe the flowing behavior of the material at high temperature, crystal slippage and polycrystal interaction are considered, the influence on the material performance is reflected from the microstructure evolution level, and the problem that the influence on the macroscopic mechanical performance of a microstructure is difficult to capture in welding multiphase metal material simulation is solved; two-dimensional representation is obtained through a metallographic experiment, the Young modulus and rigidity matrix parameters are accurately calculated by combining forward stretching and shear simulation, the rigidity matrix precision is improved, a temperature field area is divided, stress evolution and residual stress are calculated by combining a thermal-elastic-plastic model, and the welding thermal stress calculation precision is improved.

The invention relates to the technical field of metal material plastic forming, and discloses an extrusion feeding device, an extrusion forming system and a control method.The extrusion feeding device comprises a loading module and a feeding driving module, and the loading module is arranged between an extrusion driving device and an extrusion forming device; a plurality of loading parts used for loading bars are distributed on the loading module, the plurality of loading parts extend and penetrate in the first direction, the loading module is provided with a heating assembly, and the heating assembly is used for heating the bars of the plurality of loading parts; the feeding driving module is used for driving the loading module to move in the direction perpendicular to the first direction so as to control the loading module to move out of or move into the working position between the extrusion driving device and the extrusion forming device. According to the invention, the heating assembly and the plurality of loading parts are adopted, bar material supplement and temperature stabilization are completed in the extrusion stroke, the extrusion temperature of the bar material can be accurately controlled, and the controllability of extrusion process conditions is ensured.

The invention provides a friction-resistant high-entropy alloy composite coating and a preparation method thereof, and belongs to the technical field of metal surface modification. A FeCoCrNiMox (x is greater than or equal to 0.18 and less than or equal to 0.25) high-entropy alloy is taken as a main component of composite powder, graphene is taken as an additive phase, and the FeCoCrNiMox high-entropy alloy composite coating is prepared on the surface of a matrix by adopting a laser cladding method. The graphene added in the composite powder can generate carbides in situ under the action of laser cladding, and second phase strengthening, solid solution strengthening and fine grain strengthening are generated, so that the friction resistance of the surface of the matrix is remarkably improved. The preparation method is easy to operate and low in cost, the prepared composite coating is high in bonding strength, good in toughness and plasticity and excellent in friction resistance, the surface performance of equipment can be effectively improved, safe and stable operation of the equipment is guaranteed, the service life of the equipment is prolonged, and maintenance expenditure is reduced.

The invention discloses an Al-Mg-Zn aluminum alloy plate with excellent strong plasticity and light weight characteristics as well as a preparation method and application of the Al-Mg-Zn aluminum alloy plate. The alloy comprises the following components in percentage by mass: 5.0%-5.5% of Mg, 1.5%-2.0% of Zn, 0.4%-0.5% of Mn, 0.1%-0.3% of Cu, 0.15%-0.25% of Sc, 0.1%-0.15% of Zr, 0.05%-0.15% of Ag, less than or equal to 0.1% of impurities and the balance of Al. The density is not more than 2.63 g / cm < 3 >, the tensile strength is not less than 470 MPa, and the ductility is not less than 23%. The preparation method comprises the steps of high-purity raw material smelting and casting, two-stage homogenization, hot rolling, intermediate annealing, cold rolling, solid solution treatment and single-stage aging. Wherein the total pressing amount of hot rolling is 80-85%, the total pressing amount of cold rolling is 20-35%, and the single-stage aging time is 120-140 DEG C * 16-24 h. The microstructure of the alloy is characterized in that the average size of dispersed AlSc particles is smaller than or equal to 100 nm, the area fraction of deformed grains is larger than or equal to 70%, the average size of nanometer beta-AlMg and T-Mg (Al, Zn) composite precipitated phases is smaller than or equal to 20 nm, the number density is larger than or equal to 1 * 10 < m >, the area fraction of micron-order second phases is smaller than or equal to 0.5%, and the alloy is only formed by impurity Fe. According to the method, the traditional two-stage aging process is simplified, low density, high strength and high plasticity are synchronously improved, and the method is suitable for large-scale industrial application.

The invention relates to a forging method of a high-strength, high-creep-resistance and high-structure-stability Ti1100 alloy bar, belongs to the technical field of titanium alloys, and aims to solve the problems that in the forging process of an existing method, macrosegregation is prone to occurring; at least one of the problems that the process is difficult to control due to narrowing of a machining window, forging is difficult due to great increase of deformation resistance, cracking is caused due to plasticity reduction, and the Ti1100 alloy bar is poor in structure stability and short in service time are solved. According to the forging method of the Ti1100 alloy bar, through one-heating-number blooming forging, one-heating-number grain refinement and homogenization forging and 2-4-heating-number cross-phase region forging, the problem of macrosegregation caused by high alloy element content in the forging process is solved; and the problems that the process is difficult to control due to narrowing of a machining window, forging is difficult due to great increase of deformation resistance, and cracking is caused due to plasticity reduction are solved.

The invention discloses a low-cost, flame-retardant, high-strength, high-thermal-conductivity and corrosion-resistant Mg-Al-Ca-Mn alloy and a preparation method thereof, relates to an Mg-Al-Ca-Mn alloy and a preparation method thereof, and aims to solve the problem that an existing magnesium alloy is difficult to meet the requirements of high plasticity, corrosion resistance, thermal conductivity and flame resistance at the same time. The invention provides a low-cost, high-strength, corrosion-resistant, heat-conducting and flame-retardant Mg-Al-Ca-Mn-X alloy, X is one or a combination of more of Y, Gd, La, Ce, Sm and Nd according to any ratio, the microstructure of the alloy is regulated and controlled through alloy component optimization, rare earth microalloying, a heat treatment process and a plastic deformation process, and the mechanical property of the alloy is improved. The alloy prepared by the invention has excellent mechanical property, corrosion resistance, heat-conducting property and flame retardant property. The method is applied to the field of metal materials.

The invention belongs to the technical field of metallurgical materials, and discloses austenite-martensite dual-phase steel and a preparation method and application thereof.The austenite-martensite dual-phase steel comprises, by mass, 0.1%-0.3% of C, 10%-20% of Cr, 6%-10% of Ni, 0.5%-1.5% of Al, smaller than or equal to 0.005% of P, smaller than or equal to 0.005% of S and the balance Fe. A basic strength platform is provided through dislocation strengthening, a nano precipitated phase regulates and controls phase transformation kinetics through chemical partition and enhances dislocation storage capacity, the gradual TRIP effect maintains plastic deformation capacity through phase transformation plasticity and secondary hardening, and finally the requirements for the strength and plasticity of the austenite-martensite dual-phase steel are met at the same time. And when the yield strength at the liquid nitrogen temperature exceeds 2 GPa, the plasticity exceeds 20%.