175 results about "Dynamic recrystallization" patented technology

The invention discloses an analysis method and system for a dynamic recrystallization structure form of a titanium alloy based on machine learning and a medium, and belongs to the technical field of metal material microstructure quantitative characterization, a Gleeble thermal compression test is processed on a titanium alloy to be tested, multi-modal data is collected, a DRX probability graph is output based on a DRX segmentation model, and then the characteristics of DRX are extracted. And respectively inputting the DRX features into the first-level classifier, carrying out PCA dimension reduction processing, splicing and fusing the prediction probability and the features after dimension reduction, and inputting the spliced and fused features into a second-level classifier to output a two-dimensional DRX segmentation map. Based on the FIB-SEM tomography sequence image, reconstructing a three-dimensional model of the DRX crystal grain so as to carry out consistency verification on the two-dimensional DRX segmentation image; and evaluating a correlation coefficient of the three-dimensional model and the two-dimensional DRX model, and finally carrying out three-dimensional visualization on the space aggregation of the DRX crystal grains. According to the method, the automation degree and efficiency of dynamic recrystallization proportion and type identification are remarkably improved.

The invention discloses a Ti55531 titanium alloy large-specification bar machining method. The method comprises the steps of cogging forging, intermediate forging and finished product forging. In the cogging forging process, the cast ingot alternately deforms at the temperature above and below the phase transformation point temperature, and beta grains are refined through static and dynamic recrystallization; and during recrystallization heating in the beta region, the temperature is controlled to be 30-50 DEG C above the phase transformation point so as to avoid excessive growth of beta grains. In the intermediate blank forging stage, controllable recrystallization annealing is added, and by controlling the forging temperature (15-25 DEG C below the phase transformation point), a part of primary alpha phase is properly reserved to limit rapid growth of beta crystal grains; through 2-3 times of'low + high 'circular forging at 40-60 DEG C and 15-25 DEG C below the beta transformation temperature, and in combination with beta-phase deformation recrystallization, the original beta grain size is remarkably refined, and the forging structure uniformity of a subsequent two-phase region is improved. The method for producing the Ti55531 titanium alloy large-specification (phi 350-600 mm) bar is advanced in process, short in preparation process, low in cost, good in product structure uniformity and high in batch stability.

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 discloses a structure evolution method and system for phase change recrystallization coupling of a multiphase metal material, the orientation during martensite generation is calculated through martensite crystallography, martensite growth is carried out, and then the martensite phase change result of the material in a multiphase state is predicted through a metallographic structure determination method. The method is established by utilizing a geometrical relationship between different crystal structures of alpha and beta titanium during martensite phase transformation of the titanium alloy, so that the method can be suitable for predicting martensite phase transformation and dynamic recrystallization coupling of the two-phase titanium alloy. The method can be used for predicting the proportion of martensite phases generated in the actual production process of titanium alloys of different marks, further predicts the surface performance, can remarkably reduce the cost and improve the simulation and analysis efficiency in the actual industrial production, and has important significance on computer-aided analysis and design in the part machining deformation process.

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 invention provides a nickel-based high-temperature alloy cutting microstructure prediction method based on a dislocation gradient model, and aims to realize optimization of process parameters through multi-scale modeling. The method comprises the following steps: firstly, calculating dislocation mobility under different temperature and pressure conditions by utilizing molecular dynamics simulation; and a dislocation generation and annihilation rate model is established in combination with a dislocation dynamics theory, so that a dynamic relationship between cutting strain and dislocation evolution is disclosed. And further through data fitting, a constitutive equation between the dislocation density and the material hardening behavior is constructed, and the evolution law of the dislocation cell structure is described emphatically. On an ABAQUS platform, a two-dimensional cutting model containing a thermal coupling effect is established, a dislocation density constitutive equation is embedded into a user-defined material module, and closed-loop correlation of macroscopic cutting parameters and microstructure evolution is achieved. According to the method, the dislocation density is creatively used as a cross-scale bridge, the understanding of a dynamic recrystallization and dislocation motion coupling mechanism in the cutting process is deepened, a prediction model is provided for technological parameter optimization, and the method has important engineering guiding significance for improving the integrity of the machined surface of the high-temperature alloy part.

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 invention belongs to the technical field of nickel-based alloy material processing and forming, and particularly relates to a preparation method and application of a powder metallurgy and isothermal forging In738 disc shaft ring piece. The hot isostatic pressing technology is adopted for preforming the blank, internal gaps and cracks of the material are eliminated, the structure is homogenized, element segregation is improved, the fatigue life is prolonged, and a plastic blank is provided for subsequent isothermal forging. Furthermore, the temperature difference between the blank and the mold is reduced through preheating treatment, deformation resistance sudden change caused by local chilling is avoided, and microcrack initiation is inhibited. In addition, dynamic recrystallization is promoted through isothermal forging, a fine equiaxed crystal structure is obtained, and the high-temperature strength is improved; and through solution treatment, grain coarsening is inhibited, a supersaturated solid solution is reserved, and driving force is provided for aging precipitation. And then a dual-mode gamma'phase strengthening system is formed through a two-stage aging process, and the endurance life is optimized. Therefore, the high-temperature comprehensive mechanical property of the In738 nickel-based alloy is improved, and the use requirement of the In738 nickel-based alloy at high temperature is met.

The invention relates to a layered isomeric Mg-Al-Ca-Zn magnesium alloy and a preparation method thereof, the alloy comprises the following components in percentage by mass: 0-0.6% of Zn, 1.0-1.4% of Al, 0.4-0.8% of Ca, and the balance of Mg and inevitable impurities, and has a layered isomeric structure in which coarse deformed grains and dynamic recrystallized grains are alternately distributed. The preparation method comprises the steps of burdening, crucible pretreatment, smelting, casting, homogenizing annealing and hot extrusion, and is simple in process and low in cost. According to the alloy, dynamic recrystallization is regulated and controlled through Zn grain boundary segregation, strong plasticity synergy is achieved, and the comprehensive mechanical property is excellent. Conventional equipment is adopted, and the method is environmentally friendly, easy to industrialize and suitable for the fields of aerospace, automobile lightweight and the like.

The invention provides a titanium alloy multidirectional reversing forging method based on dynamic structure regulation and control, which comprises the following steps of: pretreating a titanium alloy cast ingot and regulating and controlling an initial structure to obtain a pretreated titanium alloy cast ingot; the pretreated titanium alloy cast ingot is subjected to reversing frequency-deformation-temperature field multi-parameter coupling forging, and a forge piece is obtained; and carrying out dynamic recrystallization and solid solution-aging strengthening on the forge piece, and cooling to obtain the titanium alloy. According to the method, through multi-parameter coupling forging of reversing times, deformation and a temperature field of the titanium alloy cast ingot, the coupling refining effect of beta-phase region dynamic recrystallization and an alpha-phase lamellar structure is achieved, and the comprehensive performance such as tensile strength, toughness and fatigue performance of the titanium alloy forged piece is remarkably improved.

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 a special steel forging process microstructure intelligent prediction method based on machine learning, and relates to the technical field of microstructures. Comprising the steps of collecting process parameter data, microstructure data and dislocation motion data. And obtaining an influence coefficient according to the influence degree of the dislocation motion data on the dynamic recrystallization behavior, processing the microstructure data according to the influence coefficient to obtain optimized dynamic recrystallization behavior data, and adjusting the process parameter data according to the optimized dynamic recrystallization behavior data to obtain structure type data. And for the optimized generalized regression neural network model, inputting tissue type data, and outputting to obtain a microstructure prediction result. According to the method, the regression neural network model is optimized by using the fruit fly optimization algorithm, the microstructure prediction result can be accurately output, the influence of the dynamic recrystallization behavior on microstructure formation can be predicted, better microstructure and performance can be obtained, and the production risk is reduced for special steel forging production.

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.

The invention discloses a hot working quality intelligent prediction method based on establishment of coupling structure and deformation condition influences, and belongs to the field of metal material plastic forming processes. According to the method, the coupling influence of the microstructure state and the deformation condition is considered, the metal material hot working quality prediction method suitable for the actual machining process is established, and the problem that the hot working quality under the constant deformation condition and the non-constant deformation condition cannot be accurately predicted through an existing universal model is solved. According to the method, the dislocation density, the grain size, the dynamic recrystallization degree, the strain rate, the deformation temperature and the deformation degree serve as input variables, the power dissipation rate and the deformation instability factor serve as output variables, a BP neural network prediction structure is established, training is conducted according to the experimental result under the constant deformation condition, and the dynamic recrystallization degree is obtained. And a hot working quality intelligent prediction model influenced by the coupling tissue and the deformation condition is obtained. The prediction of the hot working quality of the metal material under the complex deformation condition in the single-pass thermal deformation process is realized, and the prediction accords with the actual engineering processing condition.

The present invention discloses a vibration mechanical forging assisted arc cladding remanufacturing method for large pile legs of marine engineering equipment. In this method, during the arc cladding process, a high-hardness cemented carbide ball is used to forge the high-temperature cladding layer. By controlling the strain rate, deformation layer thickness, dynamic recovery and dynamic recrystallization processes, the coarse columnar crystals in the cladding layer are effectively eliminated, the grains are refined, irregular pore defects and residual tensile stress are reduced, the mechanical properties of the metal repair layer are improved, and the strength and plasticity are improved at the same time, so that the repair layer can also have high mechanical properties without rolling and heat treatment. In addition, the present invention can perform transverse forging in the vertical cladding direction of the cladding layer through the reciprocating vibration of the impact gun, forming a larger forging area, effectively improving the regulation effect on the microstructure of the cladding metal, more effectively achieving the shape regulation of the cladding layer metal, and improving the mechanical properties of the repair layer.

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 provides a dynamic recrystallization deformation structure and performance multi-scale simulation method and system coupled with crystal plasticity, and the method comprises the steps: simulating a metal plastic processing process through macroscopic finite element calculation, updating the state through a macroscopic material constitutive model in the calculation process, recording the historical information related to deformation of each unit, and calculating the deformation of each unit; a microstructure plastic recrystallization model is adopted, microstructure calculation is carried out in combination with deformation historical information, tissues, textures and stress at specified intervals are output, geometric information of a macroscopic finite element is extracted, geometry is reconstructed according to finite element deformation coordinate information, and according to the corresponding tissue, texture and stress information of unit and strain state indexes, the microstructure, texture and stress information of the unit and strain state indexes is calculated. And realizing prediction display of tissue and texture distribution in an overall corresponding deformation state. According to the method, under the metal non-uniform hot working plastic deformation state, the multi-scale simulation method for the structures, textures and mechanical properties of different areas is predicted, and the method has great significance in guiding metal plastic working process design and structure property regulation and control.

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.