382 results about "Work hardening" patented technology

The invention discloses a production method of a 500MPa-grade galvanized dual-phase steel strip for an automobile bracket. The 500MPa-grade galvanized dual-phase steel strip comprises the following chemical components in percentage by mass: 0.05-0.08% of C, less than or equal to 0.25% of S , 1.5-1.8% of Mn, less than or equal to 0.020% of P, less than or equal to 0.015% of S, 0.015-0.060% of Alt, 0.01-0.25% of Cr, 0.0010-0.0030% of Ca and the balance of Fe. The production method specifically comprises the following steps: a smelting-continuous casting production process flow; a hot rolling production technological process; pickling and cold rolling; and carrying out continuous hot galvanizing and finishing processes. The 500MPa-grade galvanized dual-phase steel for the automobile bracket has the characteristics of low yield ratio, high work hardening capacity, good corrosion resistance, welding performance, no yield elongation, no room-temperature aging, high elongation and the like, and can meet the requirements of users on light-weight and high-corrosion-resistance material selection.

The invention discloses a titanium alloy based on lamellar alpha phase and nanophase precipitation and a preparation method of the titanium alloy, belongs to the field of titanium alloy materials, and aims to solve the bottleneck that strength and work hardening of a high-strength titanium alloy are difficult to cooperate. The titanium alloy comprises, by weight, 2.0%-7.5% of Al, 1.0%-6.0% of V, 1%-8% of x (x is at least one eutectoid beta stable element of Fe, Mn, Cr, Ni and Cu) and the balance Ti and impurities. And the beta-phase molybdenum equivalent [Mo] eq is controlled to be 5.0-10.0. The preparation method comprises the following steps: 1) smelting an ingot for three times in a vacuum consumable electric arc furnace, and cutting a dead head after scaling and flaw detection; (2) carrying out hot rolling at 810-950 DEG C in an alpha + beta two-phase region with the accumulative deformation amount of 75-95%, and constructing a multi-scale lamellar alpha phase, and (3) carrying out solid solution for 30-120 minutes at 700-850 DEG C, rapidly cooling at 50-250 DEG C / s, and inducing the precipitation of a nano eutectoid compound. Aging treatment is not needed, the yield strength is greater than 900 MPa, the work hardening amount is greater than 150 MPa, the elongation is greater than or equal to 15%, the process is simple and easy to industrialize, and the method can be applied to the fields of aerospace, ocean engineering and the like.

The invention relates to a heat-treated high-yield aluminum alloy material for die casting and a preparation method thereof in the technical field of cast aluminum alloy materials, the heat-treated high-yield aluminum alloy material for die casting comprises Si, Al, Fe, Mg, Zn, Ti, Zr and Sr, the components are weighed according to the mass percent, and meanwhile, the preparation method of the heat-treated high-yield aluminum alloy material comprises the steps that 1, raw materials are weighed; 2, melting the raw materials; step 3, ultrasonic stirring; step 4, casting the molten liquid; the aluminum alloy material is obtained through heat treatment, grain refinement is facilitated, the corrosion resistance of an aluminum alloy plate is improved, meanwhile, recrystallization of the alloy in the deformation and heat treatment process can be restrained, the work hardening effect of the alloy can be kept by restraining recrystallization, deformation is restrained, and the aluminum alloy material has the characteristic of high yield degree.

The invention discloses steel for high-manganese steel cutter teeth and a preparation method of the steel, and belongs to the technical field of steel for dredging equipment. The technical problem that the service life of existing steel for reamer teeth is short due to poor wear resistance and low strength is solved. The steel for the high manganese steel cutter teeth comprises the following components in percentage by mass: 0.95 to 1.35 percent of C, 0.30 to 0.80 percent of Si, 11.0 to 14.0 percent of Mn, less than or equal to 0.070 percent of P, less than or equal to 0.030 percent of S, 0.20 to 0.30 percent of Mo, 0.020 to 0.030 percent of Cr, 0.01 to 0.2 percent of Nb and the balance of Fe and inevitable impurities. When the steel for the high-manganese steel cutter teeth is subjected to an impact load, the surface can generate an extremely strong work hardening effect, so that the surface wear resistance is greatly improved, and the core part still keeps high toughness.

The invention relates to the technical field of high-strength steel production, in particular to 780MPa-grade forming-enhanced cold-rolled dual-phase steel and a preparation method thereof.The 780MPa-grade forming-enhanced cold-rolled dual-phase steel comprises the chemical components of 0.09%-0.11% of C, 0.25%-0.45% of Si, 1.9%-2.1% of Mn, smaller than or equal to 0.012% of P, smaller than or equal to 0.006% of S, 0.03%-0.05% of Als, smaller than or equal to 0.005% of N, 0.25%-0.35% of Cr, 0.015%-0.025% of Nb, 0.08%-0.12% of Cu and 0.05%-0.09% of Ni, and the ratio of Nb to Cr is 1: 10-1: 12; ceq is equal to 0.38%-0.42%, and the balance is Fe and impurities; the core objective of the invention is to enable the work hardening index n value to be greater than or equal to 0.24 through component collaborative optimization and process precise regulation and control, so that the industrial pain points of insufficient reaming performance and poor formability of the existing 780MPa-grade cold-rolled dual-phase steel are fundamentally solved, and meanwhile, the alloy cost is reduced, and the manufacturability is improved.

The invention belongs to the technical field of bimetallic composite materials, and provides a copper-aluminum bimetallic composite material and a preparation method thereof. The method comprises the following steps: coating an aluminum material with a copper strip, sealing through continuous electron beam welding, carrying out continuous equal channel angular extrusion on the copper-aluminum bimetallic material, carrying out heat treatment on the deformed copper-aluminum bimetallic material, and then carrying out extended extrusion or drawing to obtain the copper-aluminum bimetallic composite material. Aluminum is used for replacing part of copper, the overall weight of the material is reduced on the premise that the high conductivity of pure copper is kept, copper resources are saved, and the production cost is reduced. After ECAP extrusion, the strength performance of the material is improved by 3-5 times; after heat treatment, work hardening disappears, and subsequent machining treatment is facilitated; after expansion extrusion, the copper-aluminum bimetallic material is processed into a copper-aluminum bimetallic bar; and after further rolling and drawing, a bimetal plate or an ultra-fine grain wire is formed, and the material is restrained by a roller and a die hole to form an accurate size and a smooth surface.

The invention discloses a titanium carbonitride-based metal ceramic alloy with a micro-nano bicrystal plate-shaped structure and a preparation method of the titanium carbonitride-based metal ceramic alloy with the micro-nano bicrystal plate-shaped structure. Binding phase powder; a carbon-nitrogen balancing powder; the Fsss particle size of the first TiCN powder is larger than the Fsss particle size of the second TiCN powder. The interface bonding property of a hard phase and a binding phase is better, better impact toughness is achieved, TiC can effectively enhance the strength and hardness of CN of the formed binding phase-based composite material (TiM), the W element can achieve solid solution and strengthen the binding phase, the hardness of the material is improved, and the wear resistance of the material is improved; the balance carbon content can improve the hardness, strength and wear resistance of the steel, and the submicron second TiCN is used for refining grains, improving the toughness and increasing the hardness of hard particles, so that the toughness of the steel is remarkably improved, the work hardening capacity is improved, and the wear resistance of the steel is obviously improved.

The invention discloses a preparation method of a TC4ELI ultralow-temperature titanium alloy plate for spaceflight, and belongs to the technical field of titanium alloy material preparation. The invention discloses a preparation method of a TC4ELI ultralow-temperature titanium alloy plate for spaceflight. The preparation method comprises the following steps: step 1, selecting a finished cast ingot which is smelted for at least three times and has the diameter specification of phi 720-840 * L; 2, the finished cast ingot is subjected to at least three-heating-number forging treatment, and a finished plate blank is manufactured; 3, the finished plate blank is subjected to at least three-heating-number hot rolling treatment, and a semi-finished plate is manufactured; 4, the semi-finished plate is annealed and polished, and a finished plate is manufactured; step 5, carrying out temperature and flaw detection on the finished plate; according to the ultra-low-temperature TC4ELI titanium alloy plate and the preparation method thereof, by controlling multi-heating-number forging and rolling process parameters, the plate has good tissue and performance, the strength and the toughness are improved, work hardening and residual stress are effectively eliminated through reasonable annealing treatment, the room-temperature plasticity and the ultra-low-temperature toughness of the plate are improved, and the preparation technology of the ultra-low-temperature TC4ELI titanium alloy plate for spaceflight is perfected.

The invention discloses a design and preparation method of a double-phase titanium alloy, and belongs to the field of titanium alloy materials and powder metallurgy. The double-phase titanium alloy comprises the following components: less than or equal to 0.012% of C, less than or equal to 0.015% of H, less than or equal to 0.06% of N, 0.50-0.70% of O and the balance of Ti and inevitable impurities. According to the method, an HCP-FCC double-phase titanium alloy forming part is obtained by utilizing high-oxygen titanium alloy powder and combining with a laser powder bed fusion (PBF-LB / M) technology for forming, wherein the volume fraction of an FCC phase is gt; the density of the finally obtained double-phase titanium alloy reaches 99.8% or above, the tensile strength is larger than or equal to 1100 MPa, the yield strength is larger than or equal to 1000 MPa, and the ductility is larger than or equal to 20.0%. According to the double-phase titanium alloy, a certain amount of nano FCC phase is induced to be formed through interstitial oxygen solid solution elements, the nano FCC phase and an HCP matrix have a coherent relationship, the Ti-O alloy can be effectively strengthened through the HCP-FCC double-phase structure, and the excellent plasticity is kept. The double-phase titanium alloy is excellent in mechanical property and does not depend on solid solution strengthening, second-phase dispersion strengthening or work hardening ways of expensive rare metals such as V, Mo and Nb, and green, low-carbon and low-cost preparation of the titanium alloy is facilitated.

The invention relates to a high-strength complex-phase hot-rolled wire rod for a 2160MPa-grade stranded wire and a manufacturing method of the high-strength complex-phase hot-rolled wire rod, after high-carbon components containing trace Nb are rolled and spun into a wire rod, the wire rod is subjected to online molten salt micro-quenching isothermal treatment, so that the wire rod is firstly subjected to front-section molten salt treatment and enters a bainite phase region from an austenite state, part of the austenite is promoted to be converted into bainite, and then the high-strength complex-phase hot-rolled wire rod is obtained. The method comprises the following steps: carrying out high-temperature tempering on the residual austenite, carrying out post-section molten salt treatment, increasing the molten salt temperature, promoting the unconverted residual austenite to be decomposed and converted into sorbite, carrying out isothermal tempering, and finally carrying out roller way slow cooling to prepare the hot-rolled wire rod of which the microscopic structure comprises a complex-phase structure consisting of tempered bainite, ferrite and tempered sorbite, so that network carbides and martensite structures can be inhibited, and the tensile strength of the hot-rolled wire rod is improved. And the structure type and toughness are regulated and controlled on line, the tensile strength is 1472-1505MPa, the percentage reduction of area is 31%-36%, the work hardening rate and the production efficiency of the hot-rolled wire rod are improved, and the production energy consumption is reduced, so that a high-strength grade stranded wire is obtained.

The alloy wire comprises the following components in percentage by mass: 0.1 to 6.0 weight percent of Sn, 0.1 to 0.3 weight percent of Ag, 0.01 to 0.20 weight percent of Zr, 0.02 to 1.00 weight percent of Y, 0.02 to 2.00 weight percent of Ce, 0.01 to 0.80 weight percent of Eu, 0.01 to 0.50 weight percent of Rb, Y / (Ce + Eu + Rb) is more than or equal to 0.8 and less than or equal to 1.2, and the balance of Cu and inevitable impurities of which the total amount is less than or equal to 0.05 weight percent. According to the invention, Ag and Zr are added into the copper-tin alloy wire in component design, and composite rare earth elements are also added, so that the addition amount of each rare earth element is limited, and in order to further improve the processability and comprehensive performance of the alloy wire, the addition amount of each rare earth element is limited; and finally, the preparation process of vacuum melting-continuous casting technology-multi-pass drawing combined with on-line dynamic annealing process treatment is combined, so that work hardening and internal stress of the wire are eliminated, the machining precision, plasticity and conductivity of the wire are improved, the material performance is more uniform, and the subsequent deformation or cracking risk in use is reduced.

The invention relates to a high-strength and high-conductivity Cu-Zr alloy material added with trace elements and a preparation method of the high-strength and high-conductivity Cu-Zr alloy material, and belongs to the technical field of copper alloy preparation and processing. The copper alloy is prepared mainly through a combined deformation heat treatment process, the prepared copper alloy has high strength and excellent conductivity and plasticity, the heat stability of the alloy is improved, and the copper alloy can be used as a lead frame, a rectifier device, a high-temperature-resistant copper alloy material, a high-temperature-resistant copper alloy material, a high-temperature-resistant copper alloy material, a high-temperature-resistant copper alloy material, a high-temperature-resistant copper alloy material, a high-temperature-resistant copper alloy material and a high-temperature-resistant copper alloy material. The method is applied to advanced fields such as rail transit and electrical electronics.

The invention discloses a high-toughness double-phase titanium-nitrogen alloy which comprises the following chemical components in percentage by mass: 0.005% < = C < = 0.01%, 0.008% < = H < = 0.015%, 0.1% < = O < = 0.15%, 0.4% < = N < = 0.6% and the balance of Ti and inevitable impurities. According to the high-toughness double-phase titanium-nitrogen alloy, a certain amount of nanometer FCC phases are induced to be formed by means of interstitial nitrogen solid solution elements, the nanometer FCC phases and an HCP matrix have a coherent relationship, the Ti-N alloy can be effectively strengthened through an HCP-FCC double-phase structure, and excellent plasticity is kept. The high-toughness double-phase titanium-nitrogen alloy is excellent in mechanical property and does not depend on solid solution strengthening, second-phase dispersion strengthening or work hardening ways of expensive rare metals such as V, Mo and Nb, and green low-carbon low-cost preparation of titanium alloy is facilitated.

The invention belongs to the technical field of additive manufacturing, and discloses a method for improving the strength of a high-entropy alloy prepared through laser directional energy deposition through composite treatment. According to the method, in the process of forming the high-entropy alloy through additive manufacturing, plastic deformation is introduced into the high-entropy alloy prepared through laser directional energy deposition through in-situ rolling, and the alloy strength is improved in situ through the work hardening and fine grain strengthening principle; and after printing is completed, the whole sample is put into liquid nitrogen for deep cooling, and the strength is further improved. According to the method, plastic deformation can be introduced into the deposition material through in-situ rolling, so that the strength of the high-entropy alloy is improved, and the residual stress of the high-entropy alloy is further regulated and controlled in combination with subzero treatment; according to the method, the tensile strength and the yield strength of the high-entropy alloy are remarkably enhanced on the premise that the plasticity of the high-entropy alloy prepared through laser directional energy deposition is not sacrificed.

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 laser powder bed molten high-strength, high-plasticity and high-work-hardening titanium alloy and a preparation method and application thereof.The preparation method comprises the steps that two kinds of titanium alloy powder with different Mo equivalents are mixed according to a certain mass ratio to form mixed powder, and the mixed powder is put into laser powder bed melting equipment; the titanium alloy is finally obtained through layer-by-layer forming by laser powder bed melting equipment according to a slicing path and process parameters of a three-dimensional model, the microstructure of the prepared titanium alloy comprises hexagonal martensite alpha 'and orthorhombic martensite alpha', and in a preferable scheme, under the condition that heat treatment is not needed, the yield strength of the titanium alloy is larger than or equal to 950 MPa, the tensile strength is larger than or equal to 1250 MPa, and the tensile strength is larger than or equal to 1250 MPa. The alloy has the advantages of high strength, high plasticity and excellent work hardening capacity, can meet the requirements of forming and high mechanical properties of titanium alloy components in complex shapes, and is especially suitable for the fields of aerospace, automobiles, weapon armors, ships, oceans and the like, and the ductility is greater than or equal to 14%, and the work hardening capacity is greater than or equal to 250 MPa.

The invention discloses a high-performance wide precision zirconium alloy strip as well as a preparation method and application thereof. By strictly controlling the content of key elements in the zirconium alloy raw material and the structure before cold rolling, the deformation resistance is reduced, and the processing plasticity is improved; the material, the roll shape curve and the surface quality of a cold rolling working roll suitable for cold rolling of the zirconium alloy strip are strictly controlled, the rolling stability is improved, the strip thickness-rolling parameter matching relation is established in stages, the pass deformation is improved, and work hardening is reduced; small-angle oblique welding seam tailor-welding is adopted, so that welding seams sequentially pass through a rolling deformation area, the average unit pressure of the welding seams is reduced, welding seam cracking is reduced, tailor-welding coiling cold rolling stable control over the wide precision zirconium alloy strip is achieved, and machining of the precision strip with the width larger than or equal to 500 mm and the thickness smaller than or equal to 0.2 mm can be achieved.

The invention discloses a preparation method of a heterostructure high-performance metastable beta titanium alloy capable of inducing a deformation mechanism in a multilevel and sequential mode, and belongs to the technical field of metal materials. The method comprises the following steps: firstly, carrying out hot rolling in a beta single-phase region to prepare a blank and crushing coarse grains; substructures such as twin crystals and martensite are introduced through cold rolling; and through short-time annealing in a beta single-phase region, a multi-stage heterogeneous lamellar structure composed of thick equiaxed crystal grains, deformation recovery crystal grains and fine recrystallized crystal grains in an alternating manner is successfully constructed. The characteristic that twin crystals and martensite induce different stresses under different grain sizes is utilized, during deformation, thick equiaxed grains firstly start a deformation mechanism, and then fine recrystallized grains are activated; and in the later period of plastic deformation, the interior of the primary deformation strip further triggers a secondary deformation mechanism. The unique behavior of'grading-time sequence 'activation of a multi-deformation mechanism along with the increase of the dependent variable enables the metastable beta titanium alloy to keep excellent plasticity, and meanwhile, the work hardening rate is remarkably improved.

This exterior material for a power storage devices is composed of a laminate including at least a base material layer, a barrier layer, and a heat-fusible resin layer in this order, the base material layer is composed of two or more layers, the base material layer includes one or more polyester films, and the base material layer has a work hardening index of 2.5 or more and 4.5 or less in both the longitudinal direction and the width direction and a difference in the work hardening index in the longitudinal direction and the width direction of 1.4 or less.

The present invention discloses a pulse current assisted cutting system and a processing method, the system includes an electric pulse assisted processing device and a laser surface roughness online detection device; the electric pulse assisted processing device includes a high-frequency pulse generator and a fixture, the high-frequency pulse generator is connected to the fixture through a wiring cable, and the fixture is clamped on the fixture of a five-axis machining center; the laser surface roughness online detection device includes a laser roughness detection head, a holder and an oscilloscope, the holder is fixed on the tool magazine of the five-axis machining center, the laser roughness detection head is clamped on the top of the holder, the focus point points to the machined surface of the workpiece, and the laser roughness detection head is connected to the oscilloscope through a signal line. The present invention solves the problems of work hardening and severe tool wear faced by titanium alloys during processing, and can effectively ensure the stability of product quality and improve the production efficiency of titanium alloy components.

To provide a close-contact bending method to be performed on a copper plate member capable of providing a good appearance on an outer surface side of a bent part.SOLUTION: A method for close-contact bending a copper plate member having a thickness of 0.3 mm or less comprises a 180-degree bending step of folding back a folding-back piece of the copper plate member at 180 degrees with respect to a body part of the copper plate member at a bending part so as to bring the folding-back piece into tight-contact with the body part. Therein, when a thickness is t, and an outer bending radius being a radius on an outer surface side of the bending part after a 180-degree bending step is R180, a ratio R180 / t of the outer bending radius to a plate thickness is equal to or greater than a threshold value that is determined, on the basis of a work hardening factor of a copper plate member, for each material of the copper plate. When the work hardening coefficient of the copper plate member is defined to be n, the threshold value is determined according to a linear expression related to the work hardening coefficient n: A×n+B.SELECTED DRAWING: Figure 5

The invention relates to the technical field of target materials, and provides a preparation method of an AgPdCu alloy sputtering target material, which comprises the following steps: firstly melting silver and preserving heat, then adding palladium and copper, heating to 1550 DEG C and preserving heat for 1 hour; the alloy liquid is subjected to heat preservation for 1 hour, the cast ingot is poured into a mold to be cooled after being subjected to homogenizing annealing, the cast ingot is obtained, casting stress can be eliminated, the non-uniformity of an as-cast structure is improved, and a more stable material basis is provided for follow-up machining; then the cast ingot is subjected to hot rolling at high temperature and at the machining rate of 85%, coarse as-cast grains can be crushed, the structure can be refined, the material compactness can be improved, and the mechanical property of the target material can be enhanced; 5 passes are conducted, cold rolling is conducted at the machining rate of 15% in each pass, the work hardening degree is controlled through step-by-step deformation, material cracking is avoided, and meanwhile the thickness precision is guaranteed; annealing treatment is performed, so that cold rolling internal stress can be eliminated, material plasticity is recovered, and the strength and processing performance of the target material are balanced; and finally, straightening and linear cutting are carried out.

The invention discloses a turbine disc alloy fatigue life prediction method considering residual stress relaxation evolution, which comprises the following steps: determining the size of a notch-containing simulation part of a turbine disc, and carrying out size optimization based on a dangerous point and a stress gradient; establishing a three-point bending finite element model, simulating a residual stress field and a work hardening field introduced by laser shock peening (LSP), and obtaining stress-strain states after a first period and a stable period through cyclic loading; compared with the prior art, the fatigue life prediction method has the advantages that by introducing the stress-strain state after the residual stress field is stabilized and combining a Walker index correction model, the problem of prediction deviation caused by neglecting subsequent relaxation in a traditional method is solved, the fatigue life margin is accurately evaluated, and the fatigue life prediction accuracy is improved. And an optimization basis is provided for the design of the turbine disc, so that the service cycle is prolonged within a safety threshold.

The invention provides a precision seamless steel tube cold drawing process quality on-line evaluation method, and relates to the technical field of precision seamless steel tube processing, and the technical scheme is as follows: collecting hydraulic cylinder double-cavity oil pressure and steel tube displacement data in real time, and dynamically calculating five parameters including drawing force, change rate, accumulative impulse, rigidity and tensile stress; and establishing a five-stage progressive anomaly judgment mechanism by combining a drawing force reference objective function constructed by historical qualified data: firstly, capturing a pipe breakage risk based on instantaneous overrun of a drawing force change rate; secondly, the work hardening cumulative effect is recognized through the continuous abnormal frequency; and depth verification is carried out by combining an accumulated impulse boundary, a rigidity theoretical range and a material strength threshold value. The method has the beneficial effects that online monitoring of the whole process of the cold drawing process is achieved, the abnormal response speed is greatly increased, and waste of raw materials is reduced; and meanwhile, the consistency of the yield strength of the product is improved by quantifying the work hardening effect, and a process knowledge base is constructed to drive intelligent manufacturing iterative optimization.

The invention discloses an in-situ composite titanium carbide reinforced titanium-based alloy and a preparation method thereof. The in-situ composite titanium carbide reinforced titanium-based alloy comprises the following chemical components in percentage by mass: 0 < = N < = 0.010%, 0 < = H < = 0.015%, 0 < = O < = 0.2%, 0.10-0.40% of C and the balance of Ti and inevitable impurities. The preparation method comprises the following steps: mixing the titanium powder and the graphite powder, and carrying out metal laser powder bed fusion printing. According to the invention, through in-situ synthesis of nano TiC particles, the size and morphology of the TiC particles are regulated and controlled, so that the mechanical property of the titanium-based alloy is greatly improved. The titanium-based alloy with high strength and excellent elongation is obtained by using a trace interstitial element C, and is independent of solid solution strengthening, second-phase dispersion strengthening or work hardening ways of expensive rare metals such as V, Mo, Nb and the like, so that green and low-cost preparation of the titanium alloy is facilitated.

The invention relates to a cast austenite high manganese wear-resistant steel. The alloy elements of the steel are as follows by mass percentage: C: 0.7-1.3%, Si: 0.3-0.7%, Mn: 7.0-20.0%, Al: 0.03-0.4%, Cr: 0.2-1.0%, Mo: 0.1-0.6%, Ni: 2.0-7.0%, V: 0.05-0.6%, N: 0.01-0.04%, P: ≤0.04%, S: ≤0.02%, and the remainder is iron and unavoidable impurities. The present invention reasonably proportions C, Mn, Ni and Cr elements and alloys them with Mo, V, Nb, N and Re, so that the steel can obtain reliable cast austenite. Because the alloyed material crystal package is densely distributed with fine nucleation carbides such as Mo, V, Nb, N and Re, the grains are refined, and the precipitation of grain boundary carbides can be significantly reduced, thereby improving the mechanical properties. In addition, due to the presence of grain refinement and fine carbide hard points, the stacking fault energy in the process of work hardening can be effectively reduced, thereby improving the work hardening ability and increasing the wear resistance of the product.

The present invention belongs to the technical field of aluminum alloy wires, and specifically relates to a high-conductivity, heat-resistant, high-elongation aluminum alloy wire and its application. The present invention defines the composition as follows: Zr 0.065-0.075%, Er 0.11-0.14%, B 0.032-0.038%, Fe 0.040-0.048%, Si 0.041-0.045%, (V+Ti+Cr+Mn) 0.012-0.018%, and the balance is aluminum. Through the setting of alloy composition, continuous casting and rolling process and intermediate annealing process, the alloy uniformly precipitates heat-resistant dispersed phase particles during the intermediate annealing process, thereby improving the heat resistance of the aluminum alloy. Through differential temperature drawing, the work hardening of aluminum alloy wire rods can be annealed and recovered online in time, reducing the traditional offline annealing process and facilitating the continuity of drawing. Combined with a single deep cold drawing process, the shape of the finished wire is fully corrected and the surface quality is improved. The conductivity, strength and elongation are then adjusted through annealing of the finished product. Finally, through the synergistic effect of the mechanism, the aluminum alloy wire has the characteristics of high conductivity, high elongation and heat resistance.

The invention discloses a cold-drawing forming reducing device for an aluminum alloy thin-wall pipe, relates to the technical field of pipe cold drawing, and aims to solve the technical problem of insufficient functionality of a traditional cold-drawing device. An auxiliary driving rail frame is arranged on the forming machine body; tensioning driving assemblies are arranged at the two ends of the auxiliary driving rail frame. The axial inner wall gaps of the guide forming penetrating mold, the decreasing mold and the limiting mold form decreasing type drawing, staged drawing treatment is formed through the forming cavity, a pipe is gradually deformed under the continuous action of the multiple molds through multi-mold staged drawing, and the work hardening process is more uniform. Compared with single-die large-deformation drawing, multi-stage drawing avoids the problem of uneven work hardening caused by excessive deformation of the local area of the pipe; and uniform work hardening can improve the overall strength and hardness of the pipe, and meanwhile, certain toughness is kept, so that the pipe has better comprehensive performance in subsequent use.

The invention discloses a method for improving the strength of a narrow-gap laser welding joint. The method comprises the specific steps that S1, firstly, laser welding is used for completing narrow-gap laser welding; s2, electric pulse treatment is carried out on a welding seam formed after welding; and S3, finally, the weld joint is subjected to hot rolling treatment, and the weld joint in the step S3 is subjected to hot rolling treatment for multiple times. After welding, electric pulse treatment is firstly carried out, then hot rolling treatment is carried out, and the strength of a sample can be improved through work hardening generated in the rolling process. Through rolling treatment, the grain size of the sample is changed, the dislocation density is increased, the texture strength is improved, and the Schmidt factor is reduced, so that the strength of the sample is improved; equipment used in the method is simple in structure, easy and convenient to operate and short in consumed time, and the whole treatment process is efficient and rapid.