93 results about "Severe plastic deformation" patented technology

The invention discloses a preparation method of a medical titanium-zirconium alloy bar wire. The preparation method comprises the processes of ingot casting, forging, quenching, hot rolling, quenching, cold rolling, recrystallization annealing, severe plastic deformation, drawing, straightening, annealing and surface treatment. The microstructure of the alloy is regulated and controlled by introducing high-density defects into the material through severe plastic deformation and combining quenching heat treatment, preparation of the titanium-zirconium alloy with high strength and plasticity and good fracture toughness is achieved, and equiaxial ultra-fine grain titanium-zirconium alloy bars and wires with the diameter ranging from 1 mm to 8 mm and the length larger than 600 mm can be produced in batches. High strength and high fatigue strength can be obtained, and the requirements of dental medical instruments for raw materials are met.

The invention discloses a preparation method of an ultra-fine grain copper target material, which comprises the following steps: step 1, sequentially cleaning and polishing an oxygen-free copper plate to obtain a pre-rolled plate; secondly, the two pre-rolled plates are overlapped and fixed, then multi-pass rolling is conducted at the temperature below the recrystallization temperature of the oxygen-free copper plate, and rolled plates are obtained; thirdly, the rolled plate is cut from the middle, then the first step and the second step are repeated for multiple times, and a machined plate is obtained; and fourthly, the machined plate is subjected to recovery annealing and then is sequentially straightened, machined and cleaned, and the ultra-fine grain copper target material is obtained. According to the method, the copper plate is subjected to severe plastic deformation by adopting an accumulative roll-bonding technology, the refining limit of a traditional machining mode on the grain size is broken through through large dependent variable, super refining of the grain size of pure copper is achieved, the ultra-fine grain target material is obtained, used equipment is simple, the size of a prepared sample is large, continuous industrial production of ultra-fine grain plates can be achieved, and the method is suitable for industrial production. And the method is a very potential production technology for industrialization of the ultra-fine grain target material.

The present invention relates to the technical field of functional property modification of high-temperature shape memory alloys, and in particular to a method for improving the superelasticity of NiTiHf high-temperature shape memory alloys. The method specifically comprises the following steps: sequentially subjecting NiTiHf high-temperature shape memory alloy ingots to homogenization treatment, rolling treatment, and electric pulse treatment. The present invention couples rolling with electric pulses and precisely controls parameters such as temperature, time, and frequency, thereby successfully achieving a NiTiHf high-temperature shape memory alloy with significantly improved superelastic properties without the need for severe plastic deformation treatment and long-term medium and high temperature heat treatment. Compared with the cast NiTiHf high-temperature shape memory alloy, in addition to significantly improving the superelastic properties, the elongation and tensile strength of the alloy are also greatly improved, wherein the recoverable strain increase is more than 200%, the elongation is increased by nearly 3 times, and the tensile strength is increased by more than 10%.

The invention discloses a method for improving the oxidation resistance of nickel-based superalloy, and belongs to the technical field of metal material surface modification. Based on the high-energy transient effect of laser shock waves, the method mainly comprises the key steps of alloy surface pretreatment, laser shock peening process implementation, post-treatment and the like. Specifically, firstly, the surface of the nickel-based single crystal alloy is subjected to pretreatment such as polishing and cleaning, surface defects and pollutants are removed, and the treatment quality is guaranteed; then, according to the material characteristics and performance requirements of the nickel-based single crystal alloy, laser parameters such as laser energy, pulse width and light spot diameter are accurately set, and proper restraint layer and absorption layer materials are selected; then, high-energy pulse laser is utilized to irradiate the absorption layer, high-temperature and high-pressure plasma is induced to be generated, the plasma expands and explodes to generate strong shock waves, the shock waves act on the alloy surface, the surface material is subjected to severe plastic deformation, a residual compressive stress layer with the depth capable of reaching hundreds of micrometers is formed, meanwhile, surface grains are refined, and the microstructure is optimized; and after the strengthening treatment is completed, simple cleaning and performance detection post-treatment are carried out. Through laser shock strengthening, a special organization structure with high density and low defect density is formed on the surface of the nickel-based single crystal alloy, diffusion and invasion of oxygen atoms are effectively hindered, and the oxidation resistance of the alloy is remarkably improved. According to the method, the controllability of technological parameters is high, the strengthening effect can be accurately regulated and controlled, the treatment process is free of pollution and high in efficiency, the obtained strengthened nickel-based single crystal alloy can be widely applied to the fields such as aerospace engine hot end parts and nuclear energy equipment which have strict requirements for high-temperature oxidation resistance, the reliability of related parts is greatly improved, and the service life of the related parts is greatly prolonged.

The invention discloses a rolling deformation method for improving the mechanical property of a CoCrFeNiMo0.35 high-entropy alloy, through high-temperature severe plastic deformation, the structure of the CoCrFeNiMo0.35 high-entropy alloy is refined, meanwhile, as-cast sample structure defects such as air holes can be eliminated, the alloy structure is densified, and along with the increase of rolling reduction, the mechanical property of the CoCrFeNiMo0.35 high-entropy alloy is improved, so that the mechanical property of the CoCrFeNiMo0.35 high-entropy alloy is improved. And further refining of crystal grains is effectively promoted. This is the first main factor causing improvement of the mechanical property of the alloy. Besides, in the hot rolling deformation process, alloy grains are stretched into a flat shape in the rolling direction, the volume fraction of a sigma phase is increased along with increase of rolling reduction, the sigma phase is a common hard phase in the high-entropy alloy, and therefore improvement of the alloy strength can be promoted, and the strength of the alloy is improved. The room-temperature tensile engineering stress-strain curve of the CoCrFeNiMo0.35 high-entropy alloy corresponding to different rolling reduction amounts is shown in the figure 7. It can be seen that when the rolling reduction is increased from 10% to 50%, the yield strength and the tensile strength of the alloy are both obviously improved.

The invention relates to a method for improving high-temperature thermal stability of ferrite martensite steel and application, and relates to the technical field of nuclear structural materials.The method specifically comprises the following steps that an alloy steel ingot is sequentially subjected to forging, rolling, rolling, quenching and air cooling, and an alloy blank with a ferrite martensite structure is obtained; sequentially carrying out austenitizing at 1020-1080 DEG C, quenching, tempering at 700-750 DEG C and air cooling on the alloy blank so as to maintain a ferrite martensite structure in the alloy blank and increase the concentration of solute elements in the alloy blank; and finally, the alloy blank subjected to secondary heat treatment is subjected to severe plastic deformation processing treatment. According to the method, good plasticity can be maintained while the high-temperature tensile strength of the ferritic martensitic steel is improved, the high-temperature thermal stability is improved, and the application prospect of the ferritic martensitic steel in nuclear structural materials is improved.

The invention discloses a preparation method of a high-strength and high-conductivity aluminum alloy profile, which comprises the following steps: 1) carrying out solution treatment on an aluminum alloy raw material to obtain a supersaturated solid solution; (2) the supersaturated solid solution is subjected to low-temperature extrusion treatment, and the aluminum alloy profile is obtained; and thirdly, the aluminum alloy profile is heated, and the high-strength and high-conductivity aluminum alloy profile is obtained. According to the method, hot extrusion is replaced by low-temperature extrusion, so that the aluminum alloy profile generates a remarkable cold hardening effect, the strength of the alloy is greatly improved, meanwhile, severe plastic deformation at the extrusion temperature generates a large number of intragranular dislocations, Mg and Si elements are promoted to be quickly and fully dispersed and separated out, the alloy generates a precipitation strengthening effect, and the conductivity is improved.

The invention discloses a near-net forming friction welding method for a dissimilar metal stud based on a middle layer, which comprises the following steps of: pre-processing a similar T-shaped boss with a thread or a circular truncated cone-shaped boss without a thread section on the end surface of a workpiece with high hardness, and pre-processing a corresponding similar T-shaped groove or a circular truncated cone-shaped groove on the end surface of a workpiece with low hardness; and before welding, middle-layer alloy is placed at the upper end and the bottom of the T-like groove or the bottom of the circular-truncated-cone-shaped groove, and the welding steps comprise rotary pressing, rotary pressing and friction, sudden stop and upsetting. The intermediate layer alloy is used as a medium, direct contact friction of a welded workpiece is avoided, surface oxidation films of adjacent base metal are broken and gaps are filled through severe plastic deformation of the intermediate layer under rotary extrusion of the workpiece, and effective welding under the conditions of low upsetting friction pressure and no obvious deformation of the workpiece is achieved. And a dissimilar metal welding interface is prevented from being overheated to generate an overthick intermetallic compound, subsequent machining is omitted, near-net forming of a friction welding joint is achieved, and the production efficiency is improved.

The invention provides an ultra-fine grain titanium wire and a post-processing method thereof, and relates to the technical field of medical materials, the method is used for reducing the dislocation density of the ultra-fine grain titanium wire, and the method comprises the steps that an original ultra-fine grain titanium wire prepared through a severe plastic deformation method is obtained; the original ultra-fine grain titanium wire is fixed to a stretching device to be subjected to pre-stretching treatment; the ultra-fine grain titanium wire subjected to pre-stretching treatment is placed in an ultrasonic treatment device to be subjected to first-time ultrasonic treatment; and the ultra-fine grain titanium wire obtained after first-time ultrasonic treatment is placed in an ultrasonic treatment device to be subjected to second-time ultrasonic treatment, and the ultra-fine grain titanium wire is obtained. According to the method, the dislocation density of the ultra-fine grain titanium wire material can be remarkably reduced, meanwhile, the tensile strength and the ductility of the material are improved, the material has the low elastic modulus, the stress shielding effect of an implant can be reduced, the implant can be matched with the elastic modulus between bones, and the effectiveness of the implant is improved.

The invention discloses a high-cycle fatigue life test method and device for a thin-wall sinking locking structure, relates to the technical field of thin-wall sinking locking structures, and aims to solve the problems that a mechanical property test method for a locking structure after severe plastic deformation is lacked at present, and a test piece adopted by an existing thin-wall test is extremely easy to break. The method comprises the following steps: acquiring a first target loading load and a second target loading load of a test piece; the test piece is of a cantilever beam type structure; based on the first target loading load, the test device is adopted to carry out initial plastic strain force loading treatment on the test piece, and a target test piece is obtained; and performing a high-cycle fatigue test on the test piece by using the test device based on the second target loading load. The test piece adopted by the high-cycle fatigue life test method for the thin-wall sinking locking structure is not easy to break, and the fatigue life test of the locking structure after severe plastic deformation can be realized.

A mold for preparing large-size rare earth magnesium alloy ingot without tail shrinkage by back pressure plastic deformation includes a male mold, a female mold, a recoverable discard block and a back pressure plate connected with a pushing cylinder of the press machine. The female mold is provided with an upper mold cavity and a lower mold cavity, an upper part of the upper mold cavity is configured for placing blanks, the recoverable discard block and the male mold, and a lower part of the upper mold cavity is inclined inward to form an extrusion deformation area. The recoverable discard block is configured to be deformed to fill an extrusion deformation area and subsequently restored into the initial state of the recoverable discard block.

The invention discloses an antibacterial heterostructure stainless steel coating and a preparation method thereof, and relates to the technical field of metal material surface modification.The preparation method of the coating comprises the steps that a stainless steel plate serves as a base body, heterostructure alloy bars of different proportions are prepared through a bar insertion method, and the heterostructure alloy bars are prepared; and the heterostructure alloy bar is subjected to solid-phase coating on the surface of the matrix through friction surfacing, so that the antibacterial heterostructure stainless steel coating is obtained. Two different metals are fused through severe plastic deformation generated by friction surfacing to form a heterostructure stainless steel coating to be coated on a substrate, and the corrosion resistance and antibacterial performance of the coating can be improved by adjusting the volume ratio of the two materials. The coating prepared by the preparation method disclosed by the invention is uniformly coated on the surface of a matrix and has corrosion resistance and antibacterial property, the antibacterial rate on pseudomonas aeruginosa can reach 94.6%, and the antibacterial rate on staphylococcus aureus can reach 96.7%.

The application relates to a composite plate performance optimization method based on a roller bending-ultrasonic flattening process cycle, S1, selecting a composite plate blank with a corresponding thickness; S2, placing the composite plate blank into a heating furnace and heating; S3, repeatedly roller bending the heated composite plate blank to be rolled into a circular arc shape with a certain angle; S4, inverting and turning over the repeatedly roller-bent composite plate blank on a mold for ultrasonic flattening; S5, turning over the composite plate blank, reheating the composite plate blank after turning over, and then performing reverse roller bending and reverse ultrasonic flattening; S6, setting the heating composite plate-roller bending-ultrasonic flattening-turning over the composite plate blank-reheating-reverse roller bending-reverse ultrasonic flattening of steps S2-S5 as one cycle, and then recycling steps S2-S5 multiple times to obtain the composite plate blank. The application can eliminate residual stress, break grains and improve microstructure through repeated severe plastic deformation and physical ultrasonic vibration, so as to improve the performance of the plate blank.

This invention discloses a two-step oscillating hot-pressing sintering method for WC-Co cemented carbide. Specifically, the method involves: loading WC-Co cemented carbide mixed powder into a mold and pre-pressing it; firstly, holding the powder at 800°C in a vacuum environment to degas and pre-sinter the billet; then applying unidirectional oscillating pressure to the billet through the mold and raising the temperature to 1100°C for solid-state sintering. Dynamic pressure causes WC particles to rearrange, and Co particles undergo severe plastic deformation under the pressure of the WC particles, further increasing the relative density of the billet; finally, the temperature is raised to 1300-1350°C to form a WC-Co eutectic liquid phase. Dynamic pressure drives further particle rearrangement, and the eutectic liquid phase uniformly fills the gaps between WC particles, completing the sintering process. This invention improves the three-dimensional spatial distribution uniformity of the Co phase, eliminates residual porosity, effectively inhibits abnormal growth of WC grains, and produces cemented carbide with excellent strength and toughness.

The application discloses a strain-induced supersaturated solid solution analysis method for a non-miscible alloy system based on mixed entropy evolution, and the method comprises the following steps: for a target A-B binary alloy, a mixed entropy-component relationship diagram of the target A-B binary alloy is drawn; the average component and the initial equilibrium phase component point of the target A-B binary alloy are calibrated in the diagram; based on the increase of the mixed degree of the entropy generation driving force, the two-phase components are predicted to evolve in the entropy increase direction during a severe plastic deformation process, until a single-phase supersaturated solid solution is formed. Based on the irreversible thermodynamic principle, the severe plastic deformation process is defined as a continuous external entropy generation source for driving the evolution of the system, through the analysis of the dynamic competition mechanism of element mixing and element demixing dominated by the entropy generation source, the formation mechanism of the supersaturated solid solution is revealed, and the application provides a universal theoretical tool for understanding and predicting the supersaturated solid solution behavior of the non-miscible alloy system under the severe plastic deformation.

The invention provides a metal bipolar plate forming device and method, and solves the technical problem that a material of an existing metal bipolar plate is subjected to severe plastic deformation in the die forming process, and local fracture is easily caused. The forming device is provided with a force transmission mechanism, the force transmission mechanism is provided with a force transmission plate, a force transmission rod and an edge pressing plate, and the force transmission plate is arranged between the upper die bottom plate and the upper die plate; the upper die bottom plate is connected with the force transfer plate through a hydraulic spring; the upper surface of the force transmission plate is connected with an ejector rod, the upper end of the ejector rod penetrates through the force transmission plate and extends out, and the force transmission plate is slidably connected with the ejector rod. One end of the dowel bar is connected with the dowel plate, the other end of the dowel bar downwards penetrates through the second through hole of the upper die plate and extends out to be connected with the edge pressing plate, the upper die plate is in sliding connection with the dowel bar, and the edge pressing plate is arranged above the lower die plate; the invention can be widely applied to the technical field of metal bipolar plates.

The invention discloses a method for improving a strip-shaped abnormal structure of a TC1 titanium alloy sheet. The method comprises the following steps: step 1, cogging, heating and rolling above a phase transformation point; 2, plate homogenization treatment is conducted above the phase transformation point; 3, reheating is conducted below the phase transformation point, and rolling operation with the deformation larger than or equal to 50% is executed; 4, recrystallization heat treatment is carried out; and 5, a finish rolling process (cold rolling) with the deformation being larger than or equal to 40% is conducted. By controlling the rolling temperature and the rolling deformation, the strip-shaped abnormal structure of the TC1 thin plate can be effectively improved, and the plate structure tends to be a uniform and fine two-phase region machining structure. The deformation resistance of the material can be effectively reduced by regulating and controlling the rolling temperature, internal stress caused by severe plastic deformation in the rolling process is reduced, and uniform deformation of the material is guaranteed. And by controlling the rolling deformation amount, crystal grains in the plate can be fully crushed, and abnormal structures are eliminated.

The invention relates to a method for recovering metal by using EB (electron beam) smelting rapid continuous casting extrusion severe deformation, which comprises the following steps: cleaning and classifying recovered metal reworked materials, respectively proportioning and mixing, adding into an electron beam cold bed furnace for smelting, keeping the temperature of the obtained metal liquid by an electromagnetic pump, and transferring into a subsequent continuous casting extrusion severe plastic deformation device; the severe plastic deformation degree is larger than 2, special structures and defects in the regenerated material are effectively eliminated, after short-process rapid deformation is conducted, after follow-up heat treatment and surface treatment are conducted, regenerated metal is obtained, and then waste parts and machining allowance generated after recovery enter the recycling process of the material again. The metal material can be repeatedly utilized, the whole-process use cost of the high-value material is remarkably reduced, the service performance of the metal material is comprehensively improved, and a large number of resources are saved.

The application discloses a kind of metal surface nanocrystalline preparation method and application based on controllable fretting friction, belong to material preparation technical field.The method is first to the surface of metal sample pretreatment, subsequently it is placed in fretting friction testing machine, by controlling normal load, displacement amplitude, frequency, time and environmental temperature etc.Parameter, make the pair of mating and sample surface occur fretting friction.The core is, utilize the local transient temperature rise generated in the process of fretting friction, make metal surface layer occur dynamic recrystallization while severe plastic deformation, to form nanocrystalline layer in one step, without secondary heat treatment.The application solves the problems such as long process, high energy consumption and difficult to control surface quality of traditional surface nanocrystallization technology, can prepare the uniform nanocrystalline layer with surface grain size in 200-1200nm and layer thickness in 2-30μm range, significantly improve the corrosion resistance of metal material, and process is simple, controllability is strong, and widely applicable material.

The application discloses a high-entropy layered transition layer material for titanium-steel connection and a preparation method thereof, and belongs to the technical field of alloy or non-ferrous metal processing. Flaky metals are stacked together, rolling is carried out at room temperature, the rolled product is folded along the length direction, and the rolling is recycled to a predetermined pass, and then the obtained intermediate sample is made into a bulk material; the bulk material is subjected to heat treatment-heat rolling and thinning, and finally the high-entropy layered transition layer material for titanium-steel connection is obtained. Through the method, the metals are subjected to severe plastic deformation, the layer spacing is reduced, and partial solid solution occurs between the metals after rolling. After heat treatment, element diffusion is completed and a layered non-uniform structure is maintained, and the alloy defects are further reduced through heat rolling and thinning. The application has the advantages of simple process, single-phase structure of the prepared alloy, and relatively high hardness.

The present disclosure provides a magnesium-based composite material and a method of forming the same. The method includes performing a casting process on magnesium, at least one first catalytic metal, and at least one first carbon allotrope to form a first magnesium-based solid solution; performing a severe plastic deformation on the first magnesium-based solid solution to form a second magnesium-based solid solution; and performing a high energy ball milling process on the second magnesium-based solid solution and an amorphous additive to form the magnesium-based composite material. The magnesium-based composite material includes a magnesium-based solid solution and the amorphous additive mixed with the magnesium-based solid solution. The magnesium-based solid solution includes magnesium, at least one first catalytic metal and at least one first carbon allotrope. The amorphous additive includes at least one second catalytic metal and at least one second carbon allotrope.

The invention discloses a nanocrystalline pure titanium implant design method, which comprises: carrying out severe plastic deformation on a coarse-grain pure titanium implant raw material to form a nanocrystalline material, and establishing a cylindrical implant model by using a Swiss-Nobel pure titanium implant as an implant model, describing the difference of the implant model in stress distribution by adopting a statics analysis module in an ANASY finite element software database; the invention relates to the technical field of implants.After the implant made of nanocrystalline pure titanium is loaded in the vertical direction and the cheek-tongue direction, compared with a coarse-grain pure titanium implant with the maximum equivalent stress being 56% of the strength limit of an implant material, the implant made of nanocrystalline pure titanium has the advantages that the strength of the implant is improved; a cylindrical implant model is established by taking a Swiss-Nobel pure titanium implant as an implant model, the diameter of the implant is optimized by adopting ANASY finite element software, and the maximum equivalent stress of bone tissues around the oral implant is 52.3 MPa, which is completely sufficient to meet the requirement of serving as the oral implant.

The invention relates to a high-strength and ultralow-magnetic susceptibility Au-Pt-Pd alloy wire as well as a preparation method and application thereof, and relates to the technical field of new materials. According to the preparation method, through the unique process combination of smelting, homogenization, severe plastic deformation and specific aging, the problem of contradiction between the alloy strength and the ultralow magnetic susceptibility is successfully solved, and the prepared Au-Pt-Pd alloy wire has the strength and the ultralow magnetic susceptibility far higher than those of a traditional Au-Pt alloy and still keeps certain plasticity.

The invention relates to a preparation method and device of a nano-structure magnesium alloy block material, and adopts the technical scheme that an incompletely-compact semi-solid magnesium alloy block material repeatedly passes through a titanium mesh under the action of electric pulse and pressure, and the internal microstructure of the incompletely-compact semi-solid magnesium alloy block material is repeatedly cut, so that the nano-structure magnesium alloy block material is prepared. And finally, the magnesium alloy block material is completely densified at a certain temperature and pressure. The method has the advantages that 1, through the scheme of the invention, the construction of a magnesium alloy block material from a semi-solid state to a solid state and from a micron level to a nano level microstructure is realized; 2, in the scheme of the invention, for the preparation of a magnesium alloy block material, equipment with overlarge tonnage is not needed, and severe plastic deformation is realized; and 3, in the implementation process of the scheme, the magnesium alloy block material is always kept at medium and low temperature, grain growth is avoided, and the preparation efficiency is improved.

The invention discloses a nickel-vanadium alloy target grain refinement method and an equal channel angular extrusion die, and belongs to the field of metal material machining severe plastic deformation. The method comprises the steps that a nickel-vanadium cast ingot is subjected to homogenizing annealing (1200 DEG C / 2 h, AC), then 8-pass extrusion is conducted through a BC path, and the total deformation is 165%. Each pass of extrusion is divided into three stages, the extrusion rates of the first four passes are the same, and the extrusion rates of the last four passes are relatively slow. The extrusion rate of each pass in the first four passes of extrusion is 10mm / s, 8mm / s and 6mm / s, and the extrusion rate of each pass in the last four passes of extrusion is 8mm / s, 6mm / s and 4mm / s. The equal channel angular extrusion die is composed of an L-shaped channel, the inner angle of the die is 120 degrees, and the outer angle of the die is 30 degrees. Then stress relief annealing (700 DEG C / 1 h, AC) is carried out; then large-deformation cold rolling is carried out, the deformation is 90%, and a sample is thinned to 3 mm; and then the plate is subjected to recrystallization annealing (550-850 DEG C / 1 h, AC). Compared with the prior art, the obtained structure is compact and has few defects, the structure is uniform, crystal grains are fine, and the strength is improved.

The present application belongs to the technical field of plastic processing of thin-walled aluminum alloy products, and relates to an aluminum alloy seamless gas cylinder and a manufacturing method thereof. The gas cylinder is formed by a cylinder mouth side half cylinder and a cylinder bottom side half cylinder through seamless inertia friction welding. The cylinder mouth side half cylinder and the cylinder bottom side half cylinder are both prepared by performing severe plastic deformation on an aluminum alloy cylinder body at room temperature through a low-temperature high-pressure torsion device. The shoulder and / or bottom curve surface of the cylinder is formed by layer-by-layer crystallization refinement of metal under high pressure, and a uniform nano-scale or sub-micron ultra-fine grain structure is formed in the material. The present application solves the problems of wrinkle, stacking and high scrap rate caused by difficult temperature control in the traditional hot closing process by performing layer-by-layer severe plastic deformation on the aluminum alloy cylinder body at room temperature through a low-temperature high-pressure torsion process, thereby greatly improving the forming quality and mechanical reliability of the gas cylinder.

The invention discloses a preparation method of a fine-grain high-hardness high-flatness copper plate, which comprises the following steps: (1) sequentially cleaning and polishing a high-purity oxygen-free copper plate to obtain a pre-rolled plate; (2) stacking a plurality of pre-rolled plates, fixing the edges of the pre-rolled plates, and performing multi-pass rolling at room temperature to realize accumulative ply rolling, so as to obtain rolled plates; (3) carrying out annealing treatment on the rolled plate in an inert atmosphere, and then straightening; (4) the annealed plate is subjected to laser surface melting treatment; and (5) surface chemical mechanical polishing and cleaning are carried out, and the fine-grain high-hardness high-flatness copper plate is obtained. According to the method, the copper plate is subjected to severe plastic deformation through the accumulative roll bonding technology, the refining limit of a traditional machining mode on the grain size is broken through through the large dependent variable, then through laser surface melting, the grain size of the surface of the copper plate is further reduced, meanwhile, the surface hardness is increased to 120-190 HV from 50-60 HV, the polishing efficiency is remarkably improved, and the polishing quality is improved. And finally, the high-flatness copper plate is obtained.

The invention discloses a method for regulating and controlling heterogeneous growth of a layered double-metal hydroxide film in a friction stir welding seam area, and relates to the technical field of friction stir welding corrosion protection. The method comprises the following steps: performing friction stir welding on two magnesium alloy plates to obtain a weld zone; and placing the weld zone in an LDHs growth solution for hydrothermal reaction. The reaction time is regulated and controlled through a hydrothermal method, and an MgAl-LDHs film layer grows in a weld zone. More electrochemical active sites are formed in a welding seam area due to severe plastic deformation in the welding process, more precursors are promoted to be formed in the initial growth stage, and the LDHs structure is induced to grow more compactly and more uniformly due to inherent defects of the welding seam area, so that structural optimization of an LDHs film layer is realized, and the welding seam area is better protected from being corroded.

The application belongs to the technical field of cord steel preparation, and particularly relates to a high-strength and high-plasticity cord steel and a preparation method thereof, the preparation method comprising the following steps: S1, obtaining a cord steel casting blank, heating, rolling and cooling the cord steel casting blank to obtain a cord steel wire rod, and the structure of the cord steel wire rod is a pearlite structure with an average interlamellar spacing of 95-100 nm; S2, cold drawing the cord steel wire rod to obtain a cord steel wire material, and the total surface reduction of the cold drawing is greater than or equal to 85%; and S3, heat treating the cord steel wire material to obtain the high-strength and high-plasticity cord steel, and the holding temperature of the heat treatment is 280-300 DEG C. According to the application, a pearlite matrix is obtained through alloy composition and cooling design, and severe plastic deformation is performed to construct an initial state with high defect density, low-temperature heat treatment is adopted to drive short-range diffusion of interface carbon atoms to construct a composition gradient and drive diffusion of micro-alloy elements to regulate nanometer precipitates, and the interface plasticization and precipitation reinforcement are synergized.

The present disclosure provides a magnesium-based composite material and a method of forming the same. The method includes performing a casting process on magnesium, at least one first catalytic metal, and at least one first carbon allotrope to form a first magnesium-based solid solution; performing a severe plastic deformation on the first magnesium-based solid solution to form a second magnesium-based solid solution; and performing a high energy ball milling process on the second magnesium-based solid solution and an amorphous additive to form the magnesium-based composite material. The magnesium-based composite material includes a magnesium-based solid solution and the amorphous additive mixed with the magnesium-based solid solution. The magnesium-based solid solution includes magnesium, at least one first catalytic metal and at least one first carbon allotrope. The amorphous additive includes at least one second catalytic metal and at least one second carbon allotrope.