318results about How to "Uniform tissue" patented technology

An isothermal near-net forming method of a TC4 titanium alloy aeroengine blisk comprises the following steps that (1) the surface of a TC4 titanium alloy bar is coated with a glass lubricant, and the TC4 titanium alloy bar is heated to T beta-(30-80) DEG C; 2) coating a glass lubricant on the pre-forging die and heating the pre-forging die to T beta-(30-80) DEG C; (3) the bar is loaded into a pre-forging die to be forged into an intermediate blank, at least one heating number of forging is carried out, the strain rate is smaller than or equal to 0.01 s <-1 >, and the deformation amount is 60-70%; after forging is completed, the intermediate blank is water-cooled to the room temperature; (4) the intermediate blank is heated to T beta-(30-80) DEG C; 5) coating a glass lubricant on a finish forging forming die and heating to T beta-(30-80) DEG C; the method comprises the following steps of (1) carrying out primary forging on an intermediate blank, (2) carrying out secondary forging on the intermediate blank, (3) carrying out secondary forging on the intermediate blank, (4) carrying out secondary forging on the intermediate blank, (5) carrying out secondary forging on the intermediate blank, (6) loading the intermediate blank into a final forging forming die, pressing the intermediate blank into a blisk forge piece, carrying out at least one-heating-number forging, carrying out water cooling on the blisk forge piece to room temperature, (7) carrying out solution treatment on the blisk forge piece and carrying out water cooling to room temperature, and (8) carrying out aging treatment on the blisk forge piece and carrying out air cooling to room temperature.

The invention discloses active brazing filler metal for sealing sapphire and kovar alloy and a preparation method of the active brazing filler metal. The active brazing filler metal comprises 25.0 wt%-27.5 wt% of Cu, 1.0 wt%-6.0 wt% of Ti, 1.0 wt%-5.0 wt% of Al, 0.1 wt%-1.0 wt% of B, 0.1 wt%-0.5 wt% of rare earth element RE, RE is one or more of La, Ce, Sc, Pr, Nd and Er, and the balance is Ag. The preparation method comprises the following steps: preparing silver-based pre-alloying powder by adopting a gas atomization method, mixing the alloy powder with additive element powder in a ball milling manner, sintering by utilizing vacuum pressure to obtain an alloy ingot blank, and carrying out rough rolling, intermediate annealing and finish rolling to obtain an active brazing filler metal strip with the thickness of 0.05-0.2 mm. The active brazing filler metal is well matched with the thermal expansion coefficient of sapphire, direct brazing of sapphire and Kovar alloy can be achieved, the brazing temperature is moderate, and a brazed joint is uniform in structure and free of defects such as air holes and cracks.

The invention discloses an aluminum alloy extrusion forming production process, which relates to the technical field of extrusion production, and comprises the following steps: designing an extrusion die, carrying out surface heat treatment on the extrusion die, selecting an aluminum alloy material, heating and extruding, carrying out surface treatment processing on a produced aluminum alloy profile, and packaging the aluminum alloy profile after the aluminum alloy profile is inspected to be qualified. Compared with the prior art, the method has the advantages that the grain structure of the profile can be more uniform and refined by accurately regulating and controlling the complex relation among parameters such as the extrusion temperature, the mold temperature, the extrusion speed and the lubricating condition, so that the mechanical property is enhanced, like a 6063 aluminum alloy profile, the tensile strength can be improved, the yield strength is improved, deformation or damage in the using process is effectively avoided, and meanwhile, the service life of the profile is prolonged. Good parameter matching can effectively reduce internal defects of the profile, metal can flow in a mold more smoothly, internal pores, cracks and other defects caused by non-uniform metal flow are reduced, and the surface quality is greatly improved.

The invention provides low-yield-ratio super-thick maritime work steel with excellent core low-temperature toughness and a manufacturing method of the low-yield-ratio super-thick maritime work steel, and belongs to the field of steel and iron material preparation. The low-yield-ratio super-thick marine steel with the excellent core low-temperature toughness comprises the following chemical components in percentage by mass: 0.10%-0.15% of C, 0.35%-0.45% of Si, 1.20%-1.50% of Mn, 3.00%-3.50% of Ni, 0.30%-0.50% of Mo, 0.15%-0.3% of Cr, 0.01%-0.02% of Ti, 0.030%-0.040% of V, 0.050%-0.060% of Nb, 0.0016%-0.0020% of B, 0.15%-0.25% of Cu, 0.060%-0.070% of Al, less than or equal to 0.010% of P, less than or equal to 0.004% of S, less than or equal to 0.39% of CET and the balance of Fe and inevitable impurities. According to the invention, a component design thought of a low-C, Ni-Nb-Mo-Al-B system is adopted, and a three-section rolling and quenching and tempering heat treatment process is combined. Through strict control of smelting continuous casting, controlled rolling and controlled cooling processes and quenching and tempering heat treatment parameters, the super-thick marine steel with excellent comprehensive mechanical properties is successfully prepared. The steel shows good low-temperature toughness in the core part, and meanwhile, the steel has a relatively low yield ratio. According to the low-yield-ratio super-thick maritime work steel with the excellent core low-temperature toughness, the thickness range is 80-150 mm, the yield strength is larger than or equal to 690 MPa, the tensile strength is larger than or equal to 920 MPa, the percentage elongation after fracture is larger than or equal to 20%, the yield ratio is smaller than or equal to 0.77, and the impact energy KV2 at the temperature of-60 DEG C is larger than or equal to 80 J.

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

The invention provides a preparation method of a micro TiAl alloy wire, and relates to the technical field of TiAl alloy preparation. The preparation method comprises the steps of raw material selection and treatment of a wire material, raw material twisting of the wire material, continuous warm drawing of a primary TiAl composite stranded wire, twisting of the primary TiAl composite wire, continuous warm drawing of a secondary TiAl composite stranded wire, repeated warm drawing of the TiAl composite wire, continuous extrusion of the TiAl wire and diffusion homogenization of the TiAl alloy wire which are sequentially carried out. According to the preparation method, the TiAl alloy wire with uniformly distributed components can be directly prepared at a lower temperature by combining multiple wire twisting, multiple continuous hot drawing and final diffusion homogenization annealing, the high-temperature melting process is effectively avoided, the components and the diameter of the TiAl alloy wire can be designed according to the requirements of the target TiAl alloy wire for the passes in the preparation and extrusion process of the TiAl composite wire, and the preparation process of the TiAl alloy wire is simplified. The method is high in flexibility, simple to operate, wide in application, low in cost and very suitable for large-scale industrial production.

The invention provides a spiral fluted tap which is provided with a thick handle part, a neck part and a thick-head thread part which are coaxially arranged, the helical angle beta of the thread part is greater than 40 degrees; the groove profile of the thread part is of a three-groove structure and is in a straight-line three-arc form; the screw tap is made of a high-speed steel material subjected to vacuum heat treatment and subzero treatment and is subjected to passivation treatment. The technical problems that a spiral fluted tap is unsmooth in chip rolling and discharging, short in service life, prone to being broken, unstable in performance and low in working efficiency are solved. The cutter is beneficial to numerical control multi-line grinding machining, sharp in cutting, beneficial to tight chip rolling, long in service life, high in machining stability and high in efficiency.

The invention relates to a production process of an ultrahigh-strength special-shaped barrel. The production process comprises the following steps: preparing a barrel blank according to the size; material distribution grooves are symmetrically formed in the positions, close to the two ends, of the outer side of the barrel, the sections of the material distribution grooves are triangular, the outer angle of the outer side edge of each triangle ranges from 94 degrees to 100 degrees, and the outer angle of the inner side edge of each triangle ranges from 140 degrees to 160 degrees; the local mandrel is drawn out, specifically, the heating number is 1-2, forging heating is conducted to 425-445 DEG C in each heating number, and only the part, located between the outer sides of the two material distribution grooves, of the barrel blank is drawn out; and local trestle reaming: 1-3 heating numbers, forging and heating each heating number to 425-445 DEG C, and only carrying out trestle reaming on the part of the barrel blank between the outer sides of the two material distribution grooves to drive the inner and outer diameters of flanges at the two ends of the barrel blank to grow together. According to the ultra-high-strength special-shaped barrel production process, materials are prevented from being accumulated at flanges at the two ends of a barrel body, meanwhile, the utilization rate of the materials is increased, the utilization rate of raw materials is increased to 38% from 28%, small-specification raw materials can be selected, and the forgeability, the formability and the structure are all allowed to be greatly improved.

The invention discloses a method for simultaneously optimizing the squareness and the remanence temperature coefficient of a 2: 17 type samarium-cobalt sintered magnet, and belongs to the technical field of rare earth permanent magnet material preparation. A component Sm < 1-x > RE < x > (CobalFeaCubZrc) z is designed, RE is one or more of Dy, Er, Gd, Tm and other heavy rare earth elements, and a, b, c and x meet the following relations: 0 < = x < = 0.6, 0.1 < = a < = 0.2, 0.06 < = b < = 0.12, 0.02 < = c < = 0.03, and 6.9 < = z < = 7.9. On the basis of a conventional smelting and ingot casting-isothermal annealing-powder preparation-oriented profiling-sintering-solid solution-aging process, an isothermal annealing process is added after smelting and ingot casting: the temperature is raised to 1190-1210 DEG C in a tubular furnace, isothermal annealing is performed for 5-20 hours, heavy rare earth elements are eliminated, and the influence of the stability of a 2: 17H phase on the component uniformity and magnetic performance of a magnet is improved; and substitution sites of heavy rare earth can be increased, and the residual magnetism temperature coefficient is optimized.

The invention discloses a process for improving impact toughness of Ti80 titanium alloy, and belongs to the technical field of metal heat treatment. The method comprises the steps that S1, a Ti80 titanium alloy cast ingot is subjected to upsetting and drawing, and a blank is obtained; s2, the blank obtained in the step S1 is subjected to two-heating-number rolling, and a rolled sample is obtained; s3, performing first heat treatment on the rolled sample obtained in the step S2 to obtain a heat-treated sample; and S4, carrying out secondary heat treatment on the heat treatment sample obtained in the step S3. According to the method, the Ti80 titanium alloy with the tri-state structure is prepared, the alloy toughness is greatly improved under the condition that the alloy strength is guaranteed, the Ti80 titanium alloy has more excellent impact load bearing capacity, and the application scene range of the Ti80 titanium alloy is expanded.

The invention provides an aluminum alloy wire and a preparation method thereof. The aluminum alloy wire comprises the following elements in percentage by mass: 0.1 to 7.0 percent of Zn element, 0.2 to 9.6 percent of Mg element, 0.1 to 6.0 percent of Cu element, 0.01 to 1.2 percent of Mn element, 0.1 to 2.0 percent of Fe element, 0.1 to 2.5 percent of Si element, less than or equal to 0.15 percent of inevitable impurities and the balance of Al element, the surface brightness L of the aluminum alloy wire is greater than 60, and the surface brightness color difference E is less than or equal to 0.5; the average roughness Sa is less than or equal to 0.4 mu m, and the maximum peak height Sp is less than or equal to 2.0 mu m; the aluminum alloy wire does not crack after 85% compression deformation; under the test conditions that the temperature is 35 DEG C, and the aluminum alloy wire is placed in a mixed solution of a 57g / L NaCl solution and a 10mL / L H2O2 solution to be soaked for 6 hours, the corrosion depth of the aluminum alloy wire is smaller than or equal to 10 micrometers.

The invention relates to the technical field of high-temperature alloys, and particularly discloses a smelting preparation process of a large-specification bar capable of resisting the temperature of 800 DEG C. The invention discloses a smelting preparation process of a large-specification bar resistant to the temperature of 800 DEG C. The smelting preparation process specifically comprises the following steps of vacuum induction smelting, annealing, first-time vacuum consumable smelting, electrode forging, second-time vacuum consumable smelting, consumable ingot homogenizing annealing and bar forging in sequence. According to the method, the large-size bar resistant to the temperature of 800 DEG C is prepared through the process, the bar quality is improved, the prepared large-size bar has excellent tensile property and high temperature resistance, the occurrence probability of black spots and white spots is reduced, and meanwhile homogenization control over bar components is achieved.

The invention discloses steel for a low-cost efficient gas shielded welding wire and a production method of the steel. The steel comprises the following chemical components in percentage by mass: 0.03-0.10% of C, 0.80-1.60% of Mn, less than or equal to 0.020% of S, less than or equal to 0.020% of P, 0.50-1.00% of Si, less than or equal to 0.010% of V, Ti, Nb and Alt, less than or equal to 0.030% of Cr, Ni and Cu, less than or equal to 0.0010% of Ca, less than or equal to 0.0045% of N and the balance of Fe and inevitable impurities. The production method comprises the steps of converter smelting, LF external refining, square billet continuous casting, straight roller way conveying, hot rolling spinning and air cooling packaging. The crystallizer adopts electric stirring and final stirring, the central shrinkage cavity and central segregation of a continuous casting billet are eliminated, a wire product with the specification of phi 5.0-7.0 mm is produced by adopting a heating-free direct rolling technology, and the steel for the gas shield welding wire is efficiently produced at low cost.

The invention discloses a heat treatment method for improving high-temperature strong plasticity of a Ti2AlNb alloy. The method comprises the following steps: 1, gradually cooling and forging the Ti2AlNb alloy to obtain a Ti2AlNb alloy plate; secondly, the Ti2AlNb alloy plate is subjected to solution treatment; and thirdly, the solid solution state Ti2AlNb alloy plate is subjected to aging treatment. According to the heat treatment method, the Ti2AlNb alloy is subjected to solid solution and aging heat treatment after being subjected to successive cooling forging, a microscopic structure composed of equiaxial alpha2 phases and thick and thin alternate lath O phases is obtained, optimal matching of the high-temperature and high-plasticity performance of the alloy is achieved, meanwhile, the heat treatment method is simple in process, the Ti2AlNb alloy plate formed through forging is only subjected to solid solution and aging treatment, and the heat treatment cost is low. The tensile strength at high temperature is improved, meanwhile, better plasticity is still achieved, the structure is uniform, the performance is stable, the safety under the high-temperature service condition is guaranteed, and the requirements of the aviation field and the aerospace field for the high-temperature strong plasticity are met.

The invention provides a precision forging method for an adjustable blade of an aero-engine based on titanium alloy, which can realize precision forging forming of the blade of the titanium alloy aero-engine, enables the blade profile size of a blade forging to directly reach the size of a finished product, does not need to be machined again, is high in product percent of pass and good in air passage consistency, also can keep the continuity of a metal flow line, and is suitable for large-scale production. The mechanical property and the aerodynamic performance are high, and the surface integrity and the metallographic structure meet the design requirements. The method comprises the following steps of blanking, surface cleaning, glass lubricant spraying, heating blank making, surface cleaning, glass lubricant spraying and forging, and is characterized in that the forging procedure comprises heating upsetting, heating pre-forging and heating finish forging, and the surface cleaning and glass lubricant spraying are respectively carried out after each procedure of heating upsetting, heating pre-forging and heating finish forging.

The bearing ring heat treatment process based on residual stress optimization comprises the following steps that S1, the surface of a bearing ring is cleaned, and it is ensured that the surface of the bearing ring is clean and free of oil stains and impurities; s2, sectional type heating treatment is conducted on the bearing ring, and the bearing ring is heated to the preset heat treatment temperature; s3, the bearing ring subjected to heat treatment is rapidly put into a quenching medium to be rapidly cooled; s4, the quenched bearing ring is subjected to tempering treatment; s5, the bearing ring subjected to tempering treatment is subjected to cooling treatment.The bearing ring heat treatment process can adjust stress distribution in the bearing ring, the cracking risk caused by stress concentration is reduced, generation of residual stress is reduced, release of the residual stress is promoted, the uniformity of residual stress distribution is improved, and the service life of the bearing ring is prolonged. And the residual stress can be effectively reduced, the toughness is improved, the structure is refined and the stability is improved, so that the quality and the service life of the bearing are improved.

The invention discloses a method suitable for preparing a high-strength titanium alloy with both strength and plasticity by an additive manufacturing process, which comprises the following steps of: 1, carrying out vacuum consumable electrode arc melting on raw materials twice to obtain a secondary cast ingot; secondly, the secondary cast ingot is machined into a round rod, plasma rotating electrode atomization powder manufacturing is conducted on the round rod, and titanium alloy powder is obtained; thirdly, the titanium alloy powder is subjected to electron beam additive manufacturing, and a titanium alloy sample is obtained; and fourthly, the titanium alloy sample is subjected to heat treatment, and the high-strength titanium alloy with both strength and plasticity is obtained. According to the method, the quality of powder is greatly guaranteed through front vacuum consumable electrode electric arc melting and plasma rotating electrode atomization powder preparation, then the titanium alloy sample is obtained through electron beam additive manufacturing, the structure of the titanium alloy sample is regulated and controlled through heat treatment, and the high-strength titanium alloy with the uniform structure and high plasticity is obtained; according to the prepared high-strength titanium alloy with both the strength and the plasticity, the tensile strength is larger than 1300MPa, and meanwhile, the elongation percentage of 5% or above is kept.

The invention provides a machining method for a top cover with an integrally-formed anti-explosion valve. The machining method sequentially comprises the following steps that S1, raw materials of the top cover are prepared; s2, stamping on one surface of the top cover through stamping equipment to form a circle of indented explosion-proof valve; s3, the top cover semi-finished product with the anti-explosion valve is cleaned through cleaning equipment; and S4, the cleaned semi-finished top cover is subjected to short-time annealing treatment through annealing equipment. Through short-time annealing treatment, the materials at the nicks can be recrystallized and softened, the structure is more uniform, the structures of other parts of the top cover are kept unchanged, and the bursting pressure value is reduced and more stable on the premise that the overall strength of the top cover is not changed.

The invention relates to the field of extrusion forming of piston skirts, in particular to an extrusion forming process of a large-size piston skirt of a marine diesel engine, which comprises the following steps of: placing a piston skirt raw material in a pre-forging annular die and a pre-forging lower die, pressing and moving downwards through a pre-forging convex die, forming a piston skirt pre-forging piece, taking out the pre-forging convex die, and replacing the pre-forging convex die with a finish-forging convex die; according to the method, the extrusion deformation process of the piston skirt is optimized, the internal metal deformation is smoother, the structure is more uniform, the metal flowing state of an area A with the most concentrated stress in the using process of the piston skirt is particularly improved, and the piston skirt forging is formed through downward pressing and movement of the finish-forging male die. And the overall quality is improved.

The invention belongs to the technical field of alloys, and particularly relates to a rolled-state tough titanium alloy and a preparation method thereof.The rolled-state tough titanium alloy is obtained by smelting sponge titanium, aluminum particles and a titanium-molybdenum intermediate alloy, then heating the smelted sponge titanium, aluminum particles and the titanium-molybdenum intermediate alloy and then adopting a hot rolling mode. The rolled-state tough titanium alloy obtained through the method is fine in grain and uniform in structure, all components are evenly distributed, the technical defects of as-cast-state Ti-6Al-xMo alloy are overcome, and the mechanical property is effectively improved.

The invention discloses a method for preparing a TiAl alloy cast ingot through vacuum induction melting, and belongs to the field of titanium-aluminum alloy smelting, metal is subjected to induction melting, the alloy cast ingot is subjected to overturning melting, in the power reduction process, the temperature of molten metal is reduced to 10 DEG C below the melting point, heat preservation is carried out for 30 min, electromagnetic stirring of a melt can last for a longer time, and the temperature of the molten metal is reduced to 10 DEG C below the melting point; therefore, the uniformity of metal components is improved. Then slowly cooling a stirring magnetic field of the alloy melt to 10 DEG C above the alpha phase transformation point at the speed of 10 kW / min, preserving heat for 30 min, performing single-phase region heat preservation heat treatment at 10 DEG C above the alpha phase transformation point without causing rapid growth of alpha crystal grains, performing furnace cooling to obtain a fine fully lamellar structure with relatively good room-temperature comprehensive mechanical property and more uniform components, and then reducing the power to the minimum at the speed of 80 kW / min, so as to obtain the high-strength alloy. And finally, the macrosegregation of the cast ingot is reduced.

The invention provides a preparation method of a high-shear-strength Nb55Ti wire. The preparation method comprises the steps of ingot casting preparation, intermediate blank forging, machining, rolling, rounding and drawing, scaling and overhauling, vacuum annealing, finished product roller drawing, finished product polishing, detecting and rewinding, rivet manufacturing of a finished product, shearing and stamping, and annealing at 800-900 DEG C; a cast ingot is prepared through a vacuum consumable melting method, then an intermediate blank with a fine and uniform structure is prepared through six-heating-number upsetting and drawing, then the cast ingot is subjected to one-heating-number rolling, cold drawing and two-heating-number vacuum annealing to prepare the small-specification wire, and finally the Nb55Ti wire is high in precision, uniform in structure and consistent in force matching.

The invention discloses an aluminum-scandium alloy and a preparation method and application thereof, and belongs to the technical field of rare earth alloy sputtering target materials, metal aluminum particles and metal scandium particles are used as raw materials, high vacuum is extracted, inert gas is introduced for multiple times of electric arc melting, aluminum-scandium alloy melt with uniform components is obtained, and after the aluminum-scandium alloy melt is cooled, the aluminum-scandium alloy is obtained. The method comprises the following steps: preparing an aluminum-scandium alloy ingot, carrying out induction heating on the aluminum-scandium alloy ingot prepared by electric arc melting to completely melt the alloy so as to obtain an alloy melt, guiding the alloy melt to be injected into a mold through an argon pressure difference, naturally cooling to form a primary alloy, and carrying out homogenizing annealing on the primary alloy under a vacuum condition to obtain the aluminum-scandium alloy. And eliminating the residual internal stress of the primary alloy to obtain the aluminum-scandium alloy. The aluminum-scandium alloy prepared through the method is low in oxygen content, high in density, fine in crystal grain, uniform in structure and good in machining performance.

The invention belongs to the technical field of bar production, and particularly relates to a production method of a steel bar for a heavy-load automobile half axle, and the steel bar comprises the following chemical components in percentage by mass: 0.39-0.42% of C, 0.25-0.35% of Si, 1.45-1.70% of Mn, less than or equal to 0.013% of P, less than or equal to 0.006% of S, less than or equal to 0.25% of Cr, less than or equal to 0.25% of Ni, 0.15-0.20% of Mo, 0.06-0.10% of V, less than or equal to 0.15% of Cu and the balance of Fe and inevitable impurities. The method has the advantages that high-performance, high-purity and low-cost production of the steel bar for the heavy-duty automobile half shaft is realized through green short-process production of'ecological electric furnace + LF + RH + continuous casting 'in combination with low-carbon component design and a controlled rolling and controlled cooling process. And macrostructures and non-metallic inclusions of the finished steel meet the requirements of high-end products.

The invention relates to a material and a heat treatment method thereof, in particular to a high-strength and high-toughness alloy steel material and a heat treatment method thereof. The high-strength and high-toughness alloy steel material comprises the following components in percentage by mass: 0.14-0.17% of C, 0.5-0.6% of Si, less than or equal to 1.8% of Mn, less than or equal to 1.5% of Cr, less than or equal to 2.0% of Ni, less than or equal to 0.7% of Mo, less than or equal to 0.5% of Cu, less than or equal to 0.12% of V, 0.57-0.60% of Ceq and the balance of Fe and inevitable impurities. According to the high-strength and high-toughness alloy steel material and the heat treatment method thereof provided by the invention, the problems of insufficient material strength, hardness and low-temperature impact toughness of a core part in the prior art are solved.

The invention discloses a nickel-tungsten-tantalum alloy target material and a preparation method thereof, and belongs to the technical field of refractory metal materials. Tungsten powder, nickel powder and tantalum powder are mixed, and the nickel-tungsten-tantalum alloy target material is prepared through cold isostatic pressing and vacuum sintering. Tantalum is added on the basis of tungsten and nickel, tantalum can hinder grain growth at a high temperature and can remarkably refine grains, then isostatic cool pressing and vacuum sintering treatment are combined, the density of the prepared nickel-tungsten-tantalum alloy target material is close to theoretical density, the structure is uniform, and the average particle size of a tungsten phase is smaller than 30 micrometers. In addition, the preparation method provided by the invention is simple in process and suitable for batch production.

The invention relates to an end socket type workpiece and a heat treatment method and a special auxiliary tool thereof, and belongs to the field of metal workpiece heat treatment. The heat treatment method of the end socket type workpiece comprises the following steps: charging the end socket type workpiece with a downward opening; then heating to 800-1060 DEG C, and keeping the temperature for 1-5 hours; then cooling is carried out, the end socket type workpiece is hoisted through a special auxiliary tool, water cooling is carried out to 550-700 DEG C, and then oil cooling is carried out to 80 DEG C or below; the cooled end socket type workpiece is tempered, the tempering temperature ranges from 300 DEG C to 600 DEG C, heat preservation is conducted for 1-10 h, and air cooling is conducted to the room temperature; the special assistive device comprises an exhaust pipe, an air inlet of the exhaust pipe is located in the highest position of the inner circumferential face of the end socket type workpiece, and an air outlet of the exhaust pipe is communicated with the atmosphere. By the adoption of the heat treatment method, it can be guaranteed that the structure of the end socket type workpiece is uniform, the mechanical property is improved, the special assistive device does not participate in the heating and cooling process, the structure uniformity of the workpiece is not affected, and energy is saved.

The invention provides a forming process of a high-strength corrosion-resistant magnesium alloy pipe, and belongs to the field of alloy materials. The magnesium alloy pipe comprises the following raw materials in percentage by mass: 3.0%-5.0% of Gd, 1.5%-3.0% of Y, 1.0%-3.0% of Al, 0.3%-0.8% of Zr, 0.05%-0.1% of Mn, less than or equal to 0.2% of Cu, less than or equal to 0.15% of Fe, 0.5%-0.8% of Zn and the balance of Mg, wherein the total amount of Gd, Y and Al is gt; the mass ratio of Gd to Y to Zr is (6.5-10): (3.5-6.8): 1, and the ratio of (Fe + Zn) / Cu is 4.5-5.3; the raw materials are mixed according to the proportion and then sequentially subjected to smelting, refining, casting, solid solution heat treatment, pipe extrusion, room-temperature rotary swaging, aging heat treatment and surface machining, and then the magnesium alloy pipe is obtained. The corrosion resistance and mechanical property of the magnesium alloy pipe are remarkably improved by optimizing alloy components and combining extrusion and room-temperature rotary swaging modes.

The invention discloses a quasi-zero-stiffness nonlinear low-frequency vibration isolation metamaterial structure, a vibration isolation device and a preparation method.The quasi-zero-stiffness nonlinear low-frequency vibration isolation metamaterial structure comprises at least one pair of zither-shaped frame structures which are consistent in size and shape and coincide front and back, a vertical fold is arranged on the vertical diagonal line of one frame structure, and the vertical fold is arranged on the vertical diagonal line of the other frame structure. And the transverse diagonal line of the other frame structure is provided with a horizontal crease. The invention provides a quasi-zero-stiffness nonlinear low-frequency vibration isolation metamaterial structure which has excellent performance in the aspects of restraining low-frequency longitudinal waves, increasing vibration damping and energy absorption and the like.

The invention relates to the technical field of additive manufacturing of high-speed steel, in particular to a method for preparing superhard high-strength M42 high-speed steel through electron beam powder bed melting. According to the method, the defect problem caused by powder splashing in the printing process can be effectively avoided, so that the porosity of a formed part is reduced, the density of a sample is improved, the M42 high-speed steel formed through additive manufacturing through the method is free of cracks, high in density, good in surface quality and uniform in structure, and separation of intracrystalline nano-micron carbide can be increased.