134 results about "Dynamic recrystallization" patented technology

The invention relates to the technical field of aluminum alloy wire processing, and particularly discloses a high-modulus high-conductivity heat-resistant aluminum alloy material, an aluminum wire, a preparation method and a power transmission cable. According to the high-modulus, high-conductivity and heat-resistant aluminum alloy material provided by the invention, the nanoscale TiB2 particles and the micron-sized SiC particles are compounded in the aluminum alloy powder, a dual-reinforcement system is constructed, and the mechanical property and the electrical property of an aluminum conductor are synergistically improved. The invention further provides a preparation method of the high-modulus and high-conductivity heat-resistant aluminum conductor. According to the process, a multi-stage coupling plastic processing technology of hot extrusion, continuous rolling, drawing and surface treatment is adopted. The grain structure is refined through the dynamic recrystallization effect in the series of machining processes, oxidation film defects on the surface and in the structure are damaged through plastic deformation, the rigidity and the conductivity of the aluminum wire are further optimized, and the technical bottleneck that high modulus, high conductivity and heat resistance of traditional aluminum alloy are difficult to consider at the same time is effectively solved.

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 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 discloses a multi-scale simulation method for a thermal compression deformation behavior of TC4 titanium alloy, and belongs to the field of metal material processing simulation. Comprising the following steps: 1, carrying out thermal compression experiments at different temperatures to obtain a deformed sample; 2, analyzing the grain orientation, orientation difference angle and texture evolution of the sample by using an electron back scattering diffraction technology; 3, constructing a crystal plasticity finite element model, and simulating a polycrystalline deformation process; 4, constructing a molecular dynamics model, and simulating phase change and dislocation evolution in thermal compression and cooling processes; and 5, based on a multi-scale simulation result, hot working parameters are optimized, dynamic recrystallization and a beta-to-alpha phase change path are regulated and controlled, and grain refinement and performance homogenization are achieved. The invention discloses a correlation mechanism of the microstructure and the mechanical property in TC4 titanium alloy thermal compression deformation, and provides a theoretical basis for optimization of a thermal processing technology of a high-performance titanium alloy component in the aerospace field.

The invention relates to the technical field of metal plate rolling processing, and discloses a rolling strengthening method capable of reducing the rigidity of a metal plate, which comprises the following steps: applying an asymmetric rolling condition to an initial plate to enable the plate to generate a speed gradient in the thickness direction; the plate is subjected to one-pass large-rolling-reduction rolling, and a non-continuously-distributed shear band is formed; the rolled plate is heated to the dynamic recrystallization temperature interval of the plate, and multi-pass small-rolling-reduction warm rolling is conducted on the plate; and in the warm rolling process, dynamic recrystallization of a shear band is promoted to form a grain-refined continuous core layer, complete recrystallization of the surface structure of the plate is inhibited to keep the work hardening state of the plate, and therefore the metal plate with the rigidity lower than that of an initial plate is obtained. According to the invention, a soft core-hard shell heterostructure is constructed in the plate, high strength and low macroscopic rigidity are synergistically realized, the process controllability is strong, and the method is suitable for preparation of high-performance structural materials.

The invention relates to the technical field of aluminum alloy forging, in particular to a forging process capable of reducing reverse forging coarse grains of 6061 aluminum alloy, which comprises the following steps: acquiring a 6061 aluminum alloy ingot, homogenizing and annealing the 6061 aluminum alloy ingot at 480-520 DEG C for 12-16 hours, cooling to room temperature by water, performing ultrasonic flaw detection, performing turning surface treatment, and alternately forging and pressing in three directions, thereby obtaining the 6061 aluminum alloy. The method comprises the following steps: placing a fine-grain 6061 aluminum alloy forge piece in a graded heating furnace, completing sub-dynamic recrystallization, applying directional pressure stress of 50-80MPa to the 6061 aluminum alloy forge piece, analyzing grain boundary characteristic distribution by adopting an electron back scattering diffraction technology, and obtaining the grain boundary optimized 6061 aluminum alloy forge piece with a discontinuous coarse-grain structure through laser shock strengthening and stress relief annealing. According to the method, the problems that reverse forging coarse grains are caused by uneven strain distribution during forging and pressing, and fine grains and high-density nanoprecipitation cannot be effectively obtained and a grain boundary structure cannot be optimized due to the fact that follow-up forging, heat treatment and stress treatment parameters are difficult to accurately control can be solved.

The invention relates to the technical field of steel pipe production, and particularly discloses a production process of a seamless steel pipe special for a high-temperature-resistant and high-pressure-resistant boiler. Under preset process parameters, a clamping mechanism is used for driving a steel billet to rotate and axially feed in, and the steel billet is symmetrically and synchronously beaten through a plurality of hammer heads, so that the steel billet is formed into a round billet; heating and perforating the round billet to obtain a pierced billet; and the pierced billet is sequentially fed into a hammerhead machine and a cold-drawing machine to be subjected to heading and drawing so as to conduct sizing on the steel pipe. The steel pipe is produced by combining a hammering forging mode with a perforating mode, and a plurality of synchronous symmetrical hammers are used for hammering, so that dynamic recrystallization and grain refinement are realized, the compactness of a steel pipe material is improved, and the high-temperature resistance and the pressure resistance of the steel pipe are improved; the circular-arc-shaped hammer head is adopted to be matched with the curvature of the steel billet, stress concentration is avoided, one-time circle forging, punching and sizing of the steel billet are achieved, the advantage of procedure integration is achieved, and the production efficiency is improved.

The preparation method of the A1-grade nondestructive inspection high-impact-toughness TC4 titanium alloy large-size bar comprises the steps that a secondary finished product cast ingot is subjected to a multi-heating-number high-temperature single-phase beta-region large-deformation forging process in the cogging stage, and as-cast grains are fully crushed and refined in the modes of axial upsetting, lateral upsetting, diagonal upsetting and the like; then, high-low-high-low repeated forging is conducted at the temperature above and below the phase transformation point, grain homogenization is achieved through high-temperature dynamic recrystallization, an original grain boundary is eliminated, and deformation dead zones of a corner angle area are effectively reduced in combination with multi-heating-number diagonal drawing-out forging; and finally, multi-heating-number forging is conducted in the two-phase region, a heat treatment process is combined, the microstructure form is further optimized, and a lamellar alpha structure is controlled to guarantee the low-temperature impact performance. According to the method, the structure uniformity of the TC4 alloy bar can be remarkably improved, the A1-level nondestructive testing requirement is met, and the method has excellent axial and chordwise mechanical properties and is suitable for ocean equipment and other high-end application fields with strict requirements for the comprehensive performance of materials.

The application provides an aluminum alloy, which comprises the following components in percentage by mass: Zn 4.0-5.0%, Mg 1.2-1.8%, Cu 0.1-0.3%, Zr 0.08-0.12%, Ti 0.02-0.06%, Fe less than or equal to 0.25%, and the balance of Al. The alloy elements containing Zn 4.0-5.0%, Mg 1.2-1.8%, Cu 0.1-0.3%, Zr 0.08-0.12%, Ti 0.02-0.06% and Fe less than or equal to 0.25% are added into a smelting furnace together with pure aluminum, smelted at 700-750 DEG C to form a melt, refined by blowing in inert gas or adding a refining agent, and the gas and inclusions are removed. The application utilizes the shearing force generated by the different rotating speeds of the upper and lower rollers of a differential rolling mill to break the coarse structure, refine the grains, and increase the dislocation density. The aluminum alloy is rolled at 480-500 DEG C to reduce the deformation resistance, promote dynamic recrystallization, maintain the processing performance, and further enhance the performance by 60-70% of the total deformation. After rolling, the aluminum alloy is subjected to multi-directional forging, the strain direction is changed multiple times, the grains are broken, the structure is homogenized, and anisotropy is eliminated, so that the comprehensive performance and application range of the aluminum alloy profile are improved. The problem that the structure cannot be refined and the dislocation density cannot be increased during the rolling process is solved.

The invention discloses a forging method for regulating and controlling the structure uniformity of a TiAl alloy, and belongs to the technical field of TiAl alloy material processing. According to the method, a TiAl alloy ingot is coated with a soft sheath, X-Y-Z three-dimensional six-pass reversing forging is carried out, then the sheath is removed, long-time annealing is carried out, X-Y-Z three-dimensional six-pass reversing forging is carried out again, and a TiAl alloy forging stock with a fine and uniform equiaxed structure is obtained; according to the method, the first round of six-pass forging is conducted on the blank through the X-Y-Z three-dimensional multi-pass reversing forging technology, short-time annealing is conducted between the passes, through the mode of combining dynamic recrystallization and sub-dynamic recrystallization, evolution of a thick and large as-cast structure in a TiAl alloy ingot is promoted, a fine equiaxed structure is formed, the uniformity of the forging stock is improved, and the yield of the TiAl alloy ingot is increased. And the blank is subjected to long-time annealing treatment, growth and spheroidization of residual lamellar structures are achieved, second-round six-pass forging is conducted, the grown equiaxed structures are refined, it is ensured that the TiAl alloy forging stock has the fine and uniform equiaxed structures, and the mechanical property of the TiAl alloy forging is improved.

The invention provides an aluminum alloy which comprises the following components in percentage by mass: 4.0-5.0% of Zn, 1.2-1.8% of Mg, 0.1-0.3% of Cu, 0.08-0.12% of Zr, 0.02-0.06% of Ti, less than or equal to 0.25% of Fe and the balance of Al, alloy elements containing 4.0-5.0% of Zn, 1.2-1.8% of Mg, 0.1-0.3% of Cu, 0.08-0.12% of Zr, 0.02-0.06% of Ti and less than or equal to 0.25% of Fe and pure aluminum are added into a smelting furnace, smelting is performed at 700-750 DEG C to form a melt, inert gas is introduced or a refining agent is added for refining, gas and inclusions are removed, and the aluminum alloy is obtained. The method utilizes different rotating speeds of upper and lower rollers of a differential rolling mill to generate shearing force, crush coarse tissues, refine grains, increase dislocation density, roll at 480-500 DEG C, reduce deformation resistance, promote dynamic recrystallization, maintain processability, further enhance performance by 60-70% total deformation, perform multi-directional forging after rolling, change strain directions for multiple times, crush grains, homogenize the tissues and eliminate anisotropy, and can be used for manufacturing a high-strength steel plate. The comprehensive performance and the application range of the aluminum alloy profile are improved, and the problems that the structure cannot be refined and the dislocation density cannot be improved in the rolling process are solved.

The invention discloses an asymmetric aluminum profile extrusion process simulation method, and particularly relates to the technical field of metal forming simulation. Constructing an asymmetric profile geometric model and extracting key structure parameters; establishing a multi-cavity welding die heat-force coupling simulation model; constructing a dynamic recrystallization structure evolution model; setting initial conditions of an extrusion process and performing finite element simulation; difference comparison is carried out on the simulation result and historical working conditions, an abnormal area is identified, and a flow track feature vector is extracted; a microstructure evolution path is inversed in combination with the microstructure parameters, and a defect prediction matrix is generated; solving the optimal process parameters through a numerical optimization algorithm, and re-simulating and verifying whether the distribution of the tissue and the stress field reaches the standard or not; according to the method, prediction of tissue defects and intelligent optimization of extrusion parameters can be achieved, and the quality control capacity of the asymmetric profile extrusion process is improved.

The invention relates to the technical field of titanium alloy solid-phase pressure friction welding, in particular to a complex uniform-section titanium alloy profile deep cavity curved surface linear friction welding reinforcement process method which comprises the following steps: S1, equipment preparation: a titanium alloy Y profile and a rib plate are respectively clamped in an upsetting cylinder and a vibration cylinder of a hydraulic linear friction welding platform; the alignment precision is controlled to be smaller than or equal to 0.05 mm and the hydraulic clamping force is controlled to be smaller than or equal to 40 kN through a fine adjustment S2, parameter setting: based on finite element simulation, setting the amplitude of + / -5mm, the frequency of 50Hz, the friction pressure of 70kN, the upsetting pressure of 75kN, the upsetting time of 30s and the axial shortening amount of 5mm, and adopting a displacement control mode; according to the method, the reserved sectional area of the blank is reduced, the load and energy consumption of extrusion equipment are reduced, the manufacturing period is shortened, the material utilization rate is increased, the joint structure uniformity is improved through thermal-mechanical coupling regulation and dynamic recrystallization, the forming precision is improved, cutting waste liquid and dust emission is avoided, and the technological process is low-carbon and energy-saving.

This invention discloses a simulation method for the asymmetric aluminum profile extrusion process, specifically relating to the field of metal forming simulation technology. The method involves: constructing an asymmetric profile geometric model and extracting key structural parameters; establishing a multi-cavity welding die thermo-mechanical coupling simulation model; constructing a dynamic recrystallization microstructure evolution model; setting initial extrusion process conditions and performing finite element simulation; comparing the simulation results with historical conditions to identify abnormal regions and extract flow trajectory feature vectors; combining microstructure parameters to invert the microstructure evolution path and generate a defect prediction matrix; solving for the optimal process parameters using a numerical optimization algorithm and re-simulating to verify whether the microstructure and stress field distribution meet the standards. This method can achieve prediction of microstructure defects and intelligent optimization of extrusion parameters, improving the quality control capability of the asymmetric profile extrusion process.

The invention relates to the field of bearing steel forging, in particular to a construction method and application of a material model for predicting structural evolution of 100CrMo7-3 bearing steel in the forging process, and the model comprises an austenite grain growth model, a thermal deformation constitutive equation, an austenite dynamic recrystallization integral number model and an austenite dynamic recrystallization grain size model. By establishing the model, the whole chain prediction evolved from a microstructure to a macroscopic forging load is realized for the first time. By adopting the model, a process window can be locked only through single simulation, the grain size of the core of the forge piece is successfully compressed to be below an industry critical value, and compared with a traditional method, the forging load prediction precision is improved in a leap-over mode.

The invention provides the application of controlling the finish rolling temperature of hot finish rolling in the aspect of reducing the grain size of the sheet in the preparation of the 2A12-O state aluminum alloy sheet. And the finish rolling temperature of the hot finish rolling is 230-250 DEG C. The invention further provides a method for preparing the 2A12 aluminum alloy sheet for improving the grain size of the 2A12-O alloy sheet. By optimizing hot rolling process parameters, increasing cooling emulsion flow, improving pass deformation and strictly controlling the finish rolling temperature, low-temperature rolling of the plate in the hot finish rolling stage is achieved on the basis that the surface quality of the plate is effectively guaranteed. The process not only inhibits dynamic recrystallization of the plate in the hot rolling process, but also enhances the cold deformation energy storage of the plate, so that the grains of the plate are finer after the finished product is annealed. The rolling process is improved, low-temperature rolling of hot finish rolling is realized, cold deformation energy storage of the plate is increased, grains of the plate are fine after a finished product is annealed, and the surface quality of the plate is effectively guaranteed.

The invention relates to a preparation method of a low-cost, high-strength and high-thermal-conductivity magnesium alloy bar, and belongs to the technical field of magnesium alloys. The method comprises the following steps: homogenizing a magnesium alloy cast ingot; the magnesium alloy cast ingot comprises the following components in percentage by mass: 4.13 to 4.29 percent of Zn, 0.39 to 0.46 percent of Zr, 0.21 to 0.34 percent of Sr and the balance of Mg and inevitable impurities. And carrying out hot extrusion on the homogenized magnesium alloy cast ingot to obtain the low-cost high-strength high-thermal-conductivity magnesium alloy bar. The microscopic structure of the magnesium alloy bar obtained through hot extrusion is composed of elongated deformed crystals and fine dynamic recrystallization, the grain size of the dynamic recrystallization ranges from 1.24 micrometers to 2.42 micrometers, and a matrix contains a large number of precipitated phases. The tensile yield strength of the magnesium alloy bar ranges from 216 MPa to 287 MPa, the ultimate tensile strength ranges from 307 MPa to 344 MPa, the ductility ranges from 14.6% to 22.3%, the heat conductivity ranges from 126.5 W * m <-1 > * K <-1 > to 134.7 W * m <-1 > * K <-1 >, rare and precious metal is not contained, cost is low, and the preparation process is simple.

An ultra-low-temperature steel for hydrogen energy storage and transportation equipment and a preparation process thereof, including chemical elements with mass percentages of C: 0.06-0.1%, Ni: 6.5-10.5%, Mn: 1.0-1.5%, Cr: 0.8-1.5%, Si: 0.3-0.5%, Al: 0.3-0.5%, and the rest being Fe elements; on the basis of conventional Ni-based ultra-low-temperature steel components, the ratio is adjusted, the components are optimized, the grain refinement and dynamic recrystallization are promoted, and the low-temperature toughness of the steel is improved; the 'austenite + forging process' is applied to densify and refine the parent phase austenite (fcc phase) grains, and then through solid phase transformation, the bcc phase (ferrite or martensite) is formed from the refined parent phase; the grain ultra-refinement can significantly improve the low-temperature toughness of the steel, the grain ultra-refinement treatment increases the grain boundary, effectively hinders the crack propagation, reduces the ductile-brittle transition temperature, and significantly improves the low-temperature toughness.

This application provides a method for preparing aluminum alloy welding wire with high production efficiency, low cost, and good product performance, as well as the aluminum alloy welding wire itself. The method for preparing the aluminum alloy welding wire includes the following steps: aluminum molten metal melting, furnace refining, ultrasonic degassing, online filtration, continuous casting and extrusion, rod drawing, intermediate annealing, and finished product drawing. The continuous casting and extrusion process directly obtains the welding wire rod blank from the molten aluminum, resulting in a simple process and high yield. The aluminum alloy structure undergoes severe shear deformation and is fully broken, resulting in a dense welding wire rod blank with sufficient dynamic recrystallization, exhibiting good drawability. Only one intermediate annealing step is required to draw it to the finished product size, resulting in high production efficiency and low cost. The aluminum alloy welding wire is composed of the following components by mass percentage: Zn 4.5-5.2%, Mg 1.2-1.8%, Cu 1.5-2.0%, Mn 0.2-0.5%, Cr 0.1-0.3%, Zr 0.05-0.2%, Ce 0.05-0.15%, Y 0.05-0.15%, Si≤0.05%, Fe≤0.08%, with the remainder being Al and unavoidable impurities.

This disclosure provides a process for preparing fine-grained nickel-titanium shape memory alloy rods for medical use, comprising: forging a heated nickel-titanium alloy ingot through multiple passes, performing multiple high-temperature continuous rolling passes, and then performing thermomechanical treatment to obtain fine-grained nickel-titanium shape memory alloy rods. This invention, through a combination of specific multi-pass forging and strictly temperature-controlled high-temperature continuous rolling, utilizes a robust dynamic recrystallization mechanism to fundamentally refine and homogenize the austenitic matrix grains, and completely breaks down the continuous brittle Ti2Ni phase distributed along the grain boundaries into a randomly dispersed distribution, thereby obtaining fine-grained nickel-titanium alloy rods with high purity and excellent microstructure. This solves the practical problems caused by the coarse grains and brittle phase segregation of the original cast nickel-titanium alloy, such as easy intergranular fracture, difficult processing and forming, low yield, and poor fatigue life in medical applications.

The application discloses a manufacturing method of an ultra-low-temperature high-strength non-magnetic austenitic stainless steel rod, which comprises the following steps: forming a fine-grain protective layer on the surface of a steel ingot by radial forging, small-deformation high-frequency forging and breaking down, so as to reduce the cracking risk in the fast forging process; increasing the forging ratio by fast forging, upsetting and elongating; and making the structure of the center of the steel ingot recrystallize to a certain extent; and finally, forming the steel rod by radial forging, large-deformation low-frequency forging and breaking down, so that dynamic recrystallization occurs in the whole cross-section of the steel rod, and uniform equiaxed crystals are formed, thereby solving the problems of multiple forging times, easy surface cracking and poor structure uniformity of the ultra-low-temperature high-strength non-magnetic austenitic stainless steel rod.

The invention discloses a low-heat-damage high-entropy alloy additive manufacturing method and post-heat-treatment process based on multi-beam laser cooperative scanning, and belongs to the technical field of metal additive manufacturing. In order to solve the problems of large thermal damage, grain coarsening and weak interface bonding in the traditional laser additive manufacturing process of the high-entropy alloy, a single laser source is split into a main laser beam, a preheating laser beam and a post-heating laser beam through a light splitting technology, the three beams of laser cooperatively scan at a specific space included angle, the light spot overlapping rate is dynamically adjusted, and sequential control is combined, so that the high-entropy alloy is obtained. The preheating-melting-stepped slow cooling full-period thermal field optimization of the molten pool is realized; a nano strengthening phase and a gradient interface layer are generated in situ in a molten pool, and dynamic recrystallization is triggered by a heat treatment laser remelting process after combination, so that grains are remarkably refined, and the interface bonding strength is improved. According to the method, through multi-beam laser coordinated regulation and process optimization design, the residual stress and porosity are effectively reduced, the compactness, mechanical property and fatigue resistance of the component are improved, and the method is suitable for high-precision and high-performance manufacturing of aerospace precision components, chemical catalytic reactors and nuclear energy equipment.

This invention discloses a fine-grained, high-strength, and tough deformation heat treatment method for large-section ring components, relating to the field of aluminum alloy ring components. The key technical points are: S1: raw material proportioning; S2: raw material smelting; S3: raw material impurity removal; S4: forging and ring making; S5: ring component preheating and heat preservation; S6: rolling and grain breaking; S7: first low-temperature annealing; S8: room temperature cold rolling; S9: second low-temperature annealing; S10: cyclic rolling, solution treatment, and aging treatment. This invention introduces a multi-pass deformation heat treatment coupling process involving high-temperature rolling, low-temperature intermediate annealing, room temperature cold rolling, and second low-temperature annealing, and sets up a multi-cycle rolling annealing process. This can release the rolling internal stress of large-section ring components layer by layer, continuously break up coarse grains, induce uniform dynamic recrystallization, and avoid uneven grain structure.

The application provides a hot working method for significantly improving the dynamic recrystallization volume fraction of a nickel-based superalloy, which comprises the following steps: firstly, placing Inconel 625 alloy into a heat treatment furnace at 1000-1100 DEG C and keeping it for 30-90 min for solid solution treatment, and then water cooling; secondly, increasing the temperature of the Inconel 625 alloy after the solid solution treatment to 700-750 DEG C and keeping it for 50-100 h, and then water cooling while applying a stress of 100-160 MPa, so as to uniformly precipitate a delta phase; and finally, increasing the temperature of the Inconel 625 alloy after the aging heat treatment to 870-950 DEG C and keeping it for 2-10 min, and then hot deforming the alloy at a strain rate of 0.1-0.001 s ‑1 The application can obtain a large amount of uniformly distributed delta phase with appropriate size in a short time by applying an external stress, avoids the problem of the delta phase being distributed along the grain and being coarse in size caused by traditional aging heat treatment, ensures that the delta phase fully plays a role in the subsequent hot deformation process by using appropriate process parameters, greatly improves the dynamic recrystallization volume fraction, and has obvious advantages in grain refinement and uniform structure in the hot working process of the nickel-based superalloy.

The invention discloses an in-situ dynamic recrystallization and static recrystallization circulating additive manufacturing structure refining method, and relates to the technical field of additive manufacturing, in the process of laser direct deposition additive manufacturing, plastic deformation is synchronously applied to a high-temperature solid deposition layer, and by adjusting laser process parameters and plastic deformation process parameters, the structure of the high-temperature solid deposition layer is refined. And the thickness of a deposition layer, the depth of a molten pool, the temperature of the deposition layer and plastic strain are controlled, and alternation of dynamic recrystallization and static recrystallization is accurately controlled. According to the method, in-situ dynamic recrystallization and static recrystallization are manufactured in the laser deposition process, in-situ regulation and control of crystal grains of the additive manufacturing alloy are achieved in a dynamic recrystallization and static recrystallization multiple circulation mode, the residual stress is eliminated, the production period is shortened, the component size and precision are guaranteed, and meanwhile the production efficiency is improved. The mechanical property is obviously improved; and the anisotropy is reduced.

The application discloses a preparation method of a fine-grain high-purity large-size aluminum plane target, which comprises the following steps: hot processing, cold rolling, annealing treatment and surface treatment. Through multi-pass transverse and longitudinal rolling combined with rapid cooling, the coarse columnar crystal of an aluminum ingot is broken, dynamic recrystallization is induced, and secondary coarsening is inhibited, so that an internal dense aluminum slab is formed; the cold rolling and intermediate annealing introduce a high-density dislocation network, and the static recrystallization driving force is enhanced; the bidirectional temperature gradient annealing realizes the uniform distribution of fine grains, and the uniformity of the structure is improved; and the surface treatment ensures a smooth surface and removes impurities. The method significantly improves the mechanical strength, uniformity and defect control of the target material, meets the high-performance requirements of the large-size aluminum plane target in the manufacturing of super-large displays, optimizes the sputtering efficiency and film thickness consistency, and has remarkable economic benefits and industrial application prospects.

The invention belongs to the technical field of metal material preparation, and particularly relates to a preparation method of a reinforced and toughened magnesium-lithium alloy, which comprises the following steps: weighing magnesium, lithium, TiB2 particles, graphene nanosheets, sodium hexametaphosphate and a lithium-boron alloy, and carrying out chemical pickling, vacuum drying and low-temperature plasma activation on a magnesium block and a lithium block to obtain the reinforced and toughened magnesium-lithium alloy. Carrying out three-dimensional mixing and dispersion on the TiB2 particles and the graphene nanosheets; magnesium and lithium are heated to be molten, the dispersed TiB2 particles, graphene nanosheets, sodium hexametaphosphate and lithium-boron alloy are added, electromagnetic stirring is carried out, the obtained melt is poured into a preheated metal mold, a 0.5-1.5 T stable magnetic field is applied, then low-stress deformation is carried out, dynamic recrystallization is initiated, and finally stress relief annealing is carried out on a formed part. The tensile strength, fracture toughness and elongation of the magnesium-lithium alloy can be effectively improved, the production period is shortened, and the percent of pass is increased.

The invention discloses a TB13 titanium alloy straight wire machining process method, and relates to the technical field of wire drawing processes, and the TB13 titanium alloy straight wire machining process method comprises the specific steps that S1, cogging forging is conducted; s2, radial forging; s3, rolling is conducted; s4, wire rod heat treatment; s5, roller die cold drawing and continuous annealing are carried out; and S6, vertical electric straightening is carried out. According to the method, the means of cogging forging, radial forging, rolling, wire rod heat treatment, roller die drawing, continuous annealing, vertical electric straightening and the like are effectively combined, comprehensive balance of dynamic recrystallization and grain nucleation growth of a TB13 titanium alloy structure is achieved, and thick and large ingot casting grains are fully refined; the continuous annealing procedure in the cold drawing process is reasonably arranged, residual stress possibly generated in the drawing process of the titanium alloy wire and caused by uneven local deformation is effectively removed, the grain structure is further refined, and energy conservation and environment protection are achieved.

This invention discloses a method for fine-grained billet preparation with low extrusion ratio and synergistic annealing of difficult-to-deform high-γ′ phase superalloys, comprising the following steps: raw material purification and batching preparation – vacuum induction melting – electron beam melting pretreatment – ​​initial molten pool establishment and stabilization melting – homogenization treatment – ​​hot extrusion and annealing heat treatment. The method utilizes electron beam droplet melting directional solidification technology to prepare difficult-to-deform superalloy ingots with continuous columnar crystal structure. Taking advantage of the significantly superior dislocation storage capacity of columnar crystals compared to traditional equiaxed crystals, and combining low extrusion ratio billet preparation with subsequent precision recrystallization annealing, this method effectively avoids the problems of easy cracking, uneven microstructure, and high cost in high extrusion ratio dynamic recrystallization processes, breaking the stringent limitations of traditional processes on the lower limit of the extrusion ratio. Compared with traditional high extrusion ratio billet preparation processes, the material yield is increased from 60%–75% to 80%–90%, an increase of 15%–25%, significantly reducing the extrusion cracking scrap rate and improving the overall microstructure consistency of the bars.

The invention relates to a 27CrMoVNb alloy forge piece and a forging forming method. The forging forming method comprises the following steps that S1, a 27CrMoVNb alloy blank is prepared; s2, heating before forging, wherein the blank is heated to 350-450 DEG C, and heat preservation is conducted; s3, first-stage forging deformation is conducted, specifically, the blank is heated to 1070-1160 DEG C, heat preservation is conducted, the blank is subjected to upsetting, and then rolling is conducted; s4, second-stage forging deformation is conducted, specifically, the blank is heated to 1025-1040 DEG C, heat preservation is conducted, the blank is subjected to upsetting, and then shaping is conducted; s5, normalizing is conducted, specifically, the forge piece is heated to 780-960 DEG C, subjected to heat preservation and then cooled to the room temperature; s6, step quenching is conducted, specifically, the forge piece is heated to 520-570 DEG C in the first stage, then cooled to 430-450 DEG C in the second stage, then cooled to 350-380 DEG C in the third stage and finally cooled to 320-340 DEG C in the fourth stage, and the forge piece is cooled to the room temperature; and S7, surface machining of the forge piece is conducted, specifically, the forge piece is machined to the target size firstly, then shot blasting treatment is conducted on the forge piece, and the method has the beneficial effects that dynamic recrystallization of materials is improved, normalizing and multi-gradient quenching are combined, and the strength and hardness of the large-size forge piece are improved.