1119 results about "Stress relief" patented technology

A component (202) is disclosed that includes a body (206) and an additive manufactured (AM) metal mass (200) that includes a first section (292) and a stress relief section (294). The stress relief section (294) includes a porous region (300) having a porosity in which an open spatial volume accounts for 2% to 50% of the total volume of the stress relief section (294). The stress relief section (294) has a smaller at least one of thermal conductivity, tensile strength, ductility, and fatigue strength than the first section (292). A braze material (310) couples the AM metal specimen block (200) to a specimen block opening (204) in the body (206). The stress relief section (294) creates a low stress zone in the metal specimen block (200), which can be located near or adjacent to a high stress zone. The stress relief section (294) reduces residual stress in the metal sample block (200), which reduces related challenges to couple the metal sample block (200) to the body (206) of the component (202), particularly in the case of the use of superalloy materials.

The invention relates to a 1200MPa-grade high-strength tool steel wire rod and a manufacturing method thereof, after V-containing chemical components are designed, rolled and spun into a wire rod, the wire rod is subjected to online molten salt isothermal quenching treatment, and the wire rod is controlled to enter a bainite phase region from a high-temperature austenite state at a cooling speed greater than or equal to 32 DEG C / s; the steel wire rod with a microscopic structure comprising tempered bainite and ferrite is prepared through isothermal tempering, toughening and destressing treatment, carbide precipitation control and roller way cover opening and slow cooling, so that generation of deteriorated structures such as martensite can be avoided, the structure state can be effectively adjusted, strong plasticity matching of the steel wire rod is achieved, and the service life of the steel wire rod is prolonged. And the tensile strength is 1120-110MPa, the percentage reduction of area is 63-67%, and the steel is suitable for the application fields of manufacturing 1200MPa-grade high-strength tool steel and the like, and is favorable for being directly processed into tool parts after being subjected to cold processing molding.

The invention relates to a 1100MPa-grade high-strength tool steel wire rod and a manufacturing method thereof, the wire rod adopts a middle-carbon Nb-V-containing chemical component design, after a steel billet is rolled and spun into the wire rod according to the spinning temperature of more than or equal to 860 DEG C, online molten salt semi-quenching isothermal treatment is performed, the wire rod is controlled to be subjected to front-section molten salt treatment, and then the steel wire rod is subjected to hot rolling and hot rolling to obtain the 1100MPa-grade high-strength tool steel wire rod. According to the method, the steel wire rod enters a bainite phase region from a high-temperature austenite state at the cooling speed of more than or equal to 30 DEG C / s to form a structure taking quenched bainite as a main component, and then is subjected to rear-section molten salt heating isothermal tempering and toughening destressing treatment, and finally is subjected to roller way slow cooling to prepare the steel wire rod with a microscopic structure comprising tempered bainite and ferrite, so that the material cost can be reduced, and the production efficiency is improved. The method has the advantages that martensite brittle structures are effectively avoided, the structure state of the hot-rolled wire rod is controlled, the plasticity and cold working performance of the wire rod are improved, the tensile strength of the product can reach 980-1030 MPa, the percentage reduction of area is 61%-66%, and the product can be directly machined into tool parts after cold forming.

Provided is a method for judging geology of a time-delayed extremely intense rockburst as to deep tunnel engineering. Information about geological structures is recorded according to methods such as geological mapping and advanced geological prediction of the tunnel face. Geometric characteristics of burst craters formed during the rockburst are recorded by utilizing advanced geological drilling and profile scanning technologies in a rockburst-damaged zone. 3D geostress in the rockburst-damaged zone is measured by using a stress relief method or a hydraulic fracturing method to determine the orientation of the maximum principal stress. A 3D numerical calculation model is established based on initial geostress testing results and physical and mechanical parameters of rock and structural discontinuities obtained through on-site geological investigations. By conducting excavation simulations under different combinations of structural discontinuities and performing numerical calculation, the risk of time-delayed extremely intense rockburst disasters at current locations after tunnel excavation is judged.

The invention discloses a multilayer three-dimensional stacked circuit board and a preparation method thereof, and the method specifically comprises the steps: obtaining a substrate with a single conductive surface, and carrying out the spraying of a stress buffer layer on the conductive surface of the substrate; covering a layer of insulating material on the stress buffer layer, and forming a pattern insulating layer through photoetching; performing pulse electroplating processing on the exposed pattern of the pattern insulating layer to obtain a first circuit board; silk-screening a flexible connection layer on the pattern bonding pad layer of the first circuit board, and carrying out three-dimensional stacking processing on the flexible connection layer to obtain a second circuit board; and assembling a circuit protection layer on the second circuit board, and processing a stress release groove between the second circuit board and the circuit protection layer to obtain the multi-layer three-dimensional stacked circuit board. Through the design of the stress buffer layer and the stress release groove, interlayer stress can be reduced, circuit board breakage or cracking caused by overlarge interlayer stress is avoided, and the technical problem that large interlayer stress is generated in the circuit board preparation process in the prior art is solved.

The invention relates to the technical field of turning devices, and discloses a sheet metal turning device and a stainless steel sheet metal turning method.The sheet metal turning device comprises a lathe bed, a main shaft installed in the lathe bed, a guide rail, a feeding base and a tool rest, and is characterized in that a vibration disc, a driving assembly, a clamp and an overturning assembly are further installed in the lathe bed; and the clamp is movably mounted on the vibration disc. The driving assembly, the vibration disc, the clamp and the overturning assembly are arranged on the lathe bed, when a stainless steel metal plate workpiece is machined, rough machining is conducted firstly, then the workpiece on the main shaft is transferred and fixed to the vibration disc through the driving assembly, the clamp and the overturning assembly, and then the stress of the workpiece is eliminated through vibration; and finally, the workpiece is transferred again and fixed to the main shaft for finish machining, the turning machining of the stainless steel sheet metal part can be adapted through the rough machining, stress removing and finish machining modes, the probability of workpiece deformation is reduced, and the machining quality of products can be improved.

The invention discloses a precise connecting rod bushing forming process, which relates to the field of multi-pass spinning forming and comprises the steps of S1, blank customization, S2, die optimization, S3, blank clamping and positioning, S4, spinning roller track planning, S5, size measurement and parameter adjustment, S6, multi-pass successive approximation, S7, parameter optimization and S8, quality detection. And S9, stress relief is conducted, specifically, the connecting rod bushing obtained after spinning is put into a box-type resistance furnace to be subjected to low-temperature tempering treatment, the tempering temperature is set to range from 200 DEG C to 250 DEG C, the heat preservation time ranges from 2 hours to 3 hours, and then the connecting rod bushing is cooled to the room temperature along with the furnace. Through spinning roller track planning, size measurement, parameter adjustment and multi-pass successive approximation, it is ensured that the size precision and stability of the formed precise connecting rod bushing are improved, through stress relief, the mechanical property of the formed precise connecting rod bushing is excellent, meanwhile, a mold is optimized, stress concentration is reduced, and the production efficiency is improved. Through track planning, size measurement and parameter adjustment of the spinning roller, the production process is efficient and controllable.

The invention discloses easy-open lid punch forming equipment, which relates to the technical field of punching equipment, and comprises a machine body, a punch forming part and a conveying part, the unwinding component is arranged at the front end of the machine body and is used for releasing an aluminum coiled material; the blanking part is mounted at the front part of the machine body and is used for cutting the released aluminum coiled material into aluminum sheets with the same size; the slicing component is mounted at the rear part of the machine body and is used for prefabricating the sheets into wafers with the same shape; and the stress relieving part is mounted in the middle of the machine body and used for releasing the stress of the aluminum coiled material. According to the invention, the blanking component is arranged to blank the released aluminum coil into the aluminum sheets with the same size, and the die for blanking the aluminum coil is arranged to be of a structure with sawteeth on one side, so that the aluminum sheets with the sawtoothed edges can be blanked, and the protruding parts of the outermost edges of the front and rear sides of the sheet with the shape can be cut into complete round sheets; therefore, the areas of non-stamping parts on the front side and the rear side of each aluminum material are reduced, and the waste amount of the aluminum materials is reduced.

The invention discloses a preparation method of a graphite composite bipolar plate, which comprises the processes of raw material homogenization, preheating treatment, hot press molding, demolding, stress relief and cutting and trimming, the raw material homogenization and stress relief processes can significantly improve the yield and product quality, and the problems of low yield, poor batch stability and the like in the prior art are solved; meanwhile, conductive fillers such as graphene, carbon fibers, carbon black, carbon nanotubes and metal fibers are introduced, so that a bridging effect among graphite particles is achieved, a conductive path is broken through, contact resistance is reduced, the overall conductivity of the bipolar plate is improved, the mechanical property of the material can be improved, and the service life of the bipolar plate is prolonged. Particularly, the bending strength is obviously improved; in addition, the method is simple in process, flexible to adjust, low in special equipment requirement, low in equipment investment and suitable for popularization.

The invention discloses a processing method of a high-toughness stainless steel / carbon steel composite plate, which comprises the following steps: compounding a high-strength carbon steel plate and a stainless steel plate through a rolling compounding process under the action of laser-assisted heating; then, the stainless steel / carbon steel composite sheet is subjected to temperature control type online periodic laser surface annealing treatment, so that a corrosion-resistant structure with a non-uniform structure in which coarse grains (a soft region) and fine grains (a hard region) are alternately arranged can be obtained on the stainless steel surface layer, and the corrosion resistance of the composite plate is improved; and meanwhile, the stress relief effect induced by laser surface annealing treatment is combined with high-temperature tempering softening of a martensitic structure on the carbon steel side part at the interface, and a heterogeneous structure induced by laser surface annealing treatment can synchronously improve the obdurability of the stainless steel / carbon steel composite plate.

The utility model discloses an assembly line carrier stress relieving device which comprises a stress rod hinged to the front end of a walking frame in a carrier and a tail rod arranged at the rear end of the carrier, the lower end of the stress rod obliquely stretches out towards the rear lower portion of the carrier, and the lower end of the stress rod serves as a stress part for receiving power for pushing the carrier to advance. The tail rod extends towards the rear side of the walking frame, the tail rod on the front side carrier is used for acting on the stress rod on the rear side carrier, so that the lower end of the stress rod swings between the stress position and the disengaging position, and the disengaging position is higher than the stress position. The upper ends of the stress rods obliquely stretch out towards the upper front portion of the walking frame, a limiting structure is formed at the front end of the frame and used for limiting the stress rods so that the lower ends of the stress rods can be located at stress positions, and the tail rod is used for acting on the upper ends of the stress rods on the rear side carrier. The lower end of the stress rod swings between a stress position and a release position; the width of the tail rod is larger than that of the upper end of the stress rod.

An improved glove has both anatomically correlating stress relief zones and / or reinforced zones to add support in areas opposite the stress relief zones to keep bunching or slipping of the glove from interfering with the bending of the user's joints. The glove may have corrugated relief zones over some or all of the joints and knuckles of the hand, wherein the relief zones are formed of peaks and valleys. A relief zone can also be provided over the webbing between the thumb and the palm. The vertical or longitudinal relief zones provide for improved glove quality while keeping manufacturing difficulty and costs at a minimum.

The invention relates to the technical field of material surface engineering, and discloses a plastic surface treatment process to solve the problems that in the prior art, a plastic surface coating is poor in adhesive force and single in function, and a traditional treatment method is not environmentally friendly. The process sequentially comprises the following steps: pre-treating a base material, and obtaining a clean and stress-free base material through ultrasonic cleaning and thermodynamic stress elimination; performing low-temperature plasma surface activation, performing physical bombardment and chemical modification on the plastic surface by utilizing plasma of specific process gas in a vacuum environment, introducing a large number of active functional groups, and remarkably improving the surface energy; and preparing and applying the functional nano coating, namely forming firm covalent bonds by using the coupling agent in a coating solution containing functional nano particles and a coupling agent and the anchor points, so that the chemical coupling of the functional coating and the plastic substrate is realized.

The invention relates to a high-performance non-quenched and tempered steel bar for a fan shaft and a manufacturing method of the high-performance non-quenched and tempered steel bar, and belongs to the field of iron-based alloys. The steel comprises the following chemical components in percentage by weight: 0.37 to 0.43 percent of C, 0.30 to 0.60 percent of Si, 1.20 to 1.70 percent of Mn, less than or equal to 0.025 percent of P, 0.030 to 0.070 percent of S, less than or equal to 0.50 percent of Cr, 0.10 to 0.30 percent of Ni, less than or equal to 0.30 percent of Mo, less than or equal to 0.30 percent of Cu, 0.010 to 0.030 percent of Al, 0.005 to 0.025 percent of Ti, 0.05 to 0.15 percent of V, 0.0100 to 0.0200 percent of N, less than or equal to 0.0002 percent of H, less than or equal to 0.0015 percent of O and the balance of Fe and inevitable impurity elements. The manufacturing process comprises the steps of converter / electric furnace smelting, LF furnace refining, RH / VD furnace vacuum degassing, continuous casting, casting blank reheating, cogging rolling, flame cleaning, intermediate blank finishing, intermediate blank heating, bar rolling, cooling and stress relief tempering. The total cross-section structure of the bar is a ferrite and pearlite structure. The bending degree per meter is smaller than or equal to 0.5 mm, the surface defect depth is smaller than or equal to 0.10 mm, and the internal quality meets the A-level requirement of the GB / T4162 standard.

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 belongs to the field of medical titanium alloy material processing, and particularly relates to a preparation method of a high-strength titanium-zirconium alloy wire. The Ti-Zr alloy comprises the following chemical components in percentage by mass: 13.5-16.5% of Zr, less than or equal to 0.10% of Fe, less than or equal to 0.10% of C, less than or equal to 0.015% of H, less than or equal to 0.6% of O, less than or equal to 0.05% of N and the balance of Ti. Firstly, a round bar blank with a certain size is obtained through the procedures of smelting, forging and drawing; and then a finished wire is prepared in the modes of temperature-controlled drawing, stress relief annealing and centerless grinding. By means of the method, the high-strength titanium-zirconium alloy wire with Rm larger than or equal to 950 MPa and A larger than or equal to 10% can be obtained, the problems that the implant material Ti-Zr alloy is low in strength and the like are solved, the high-strength titanium-zirconium alloy wire for dental products can be produced through the method, and qualified raw materials are provided for the dental implant products.

The embodiment of the invention discloses a stress relief effect evaluation method based on a hydraulic fracturing ground stress test. The stress relief effect evaluation method comprises the following steps: performing ground stress inversion on a to-be-relieved stress area according to hydraulic fracturing ground stress test data to determine an initial stress field; determining a stress concentration area in the excavation process of the stress to-be-relieved area according to the initial stress field; drilling a hole in the stress concentration area, carrying out a first hydraulic fracturing ground stress test in the drilled hole, recording a first pressure time history curve, and calculating the fracture surface stress before relieving; keeping the position of the packer in the first crustal stress test unchanged, continuously performing water injection fracturing, performing the hydraulic fracturing crustal stress test at the original position again, recording a second pressure time-history curve, and calculating the fracture surface stress after the second pressure time-history curve is relieved; and comparing fracture surface stress characteristic changes before and after fracturing, and evaluating the stress relief effect of the stress to-be-relieved area according to the fracture surface stress before and after relieving. The pain point that the stress relieving effect is difficult to quantitatively evaluate in the prior art is effectively solved.

The invention belongs to the technical field of material welding, and discloses a titanium alloy welding method which comprises the following steps: pretreating a to-be-welded surface of a titanium alloy; the pretreated to-be-welded surface is subjected to sand blasting treatment and magnetron sputtering treatment, and an iron film is sputtered on the to-be-welded surface; the titanium alloy with the to-be-welded surface sputtered with the iron film is subjected to annealing treatment in the argon atmosphere; and the to-be-welded surface of the sputtering iron film is welded through a diffusion welding process. According to the characteristic that the iron element can promote mutual diffusion of the titanium alloy, surface sand blasting, magnetron sputtering, stress relief annealing and diffusion welding processes are combined, so that the titanium alloy is tight in interface connection and complete in grain, the plasticity is not obviously reduced while the strength of the titanium alloy is kept, and the requirement for large-scale and integrated aero-engines can be met.

The invention relates to the technical field of titanium alloy investment precision casting, and particularly provides a titanium alloy multistage deep blind hole investment casting method which comprises the following steps: designing an exhaust hole and a slag removal hole; establishing a model; assembling and welding; soaking the surface layer in a vacuum negative pressure environment, continuously vacuumizing, deflating after soaking, taking out the module, and rotating to uniformly control the slurry; preparing a surface layer; performing segmented grouting on the deep blind hole; making a shell from a back layer; roasting and molding; washing and drying; pouring is conducted; shell cleaning and sand blasting; sealing and welding the process holes; and performing stress relief annealing. And a dynamic vacuumizing means is adopted, and a vacuumizing device is always kept in an open state, so that the compactness of a surface layer is improved, and burrs of a casting are reduced. Through vacuum dynamic slurry immersion, segmented grouting and collaborative design of the exhaust hole and the slag removal hole, investment precision casting forming of the high-precision oil pump shell can be supported, the shell manufacturing efficiency of the multi-stage deep blind hole is improved, and the filling defect rate is reduced.

The invention provides an aluminum alloy door and window seamless welding system, which belongs to the technical field of door and window welding, and comprises a machine table, a door and window profile and a welding gun, and further comprises a positioning and grinding assembly and a dedusting and destressing assembly, welded door and window profiles do not need to be carried to independent polishing equipment, polishing is directly completed through state switching of the pressing plate, the inter-process circulation time is shortened, and positioning deviation caused by secondary clamping of traditional equipment is avoided; the functions of aluminum scrap collection and weld joint stress release in the polishing process are integrated in the pressing plate, polishing-dust removal-stress relief three-in-one synchronous treatment is achieved, the residual stress elimination effect is maximized, deformation of doors and windows in later use is effectively avoided, vibration force is transmitted through the pressing plate, and damage to the doors and windows is avoided; in addition, the vibration time is synchronous with grinding, stress relaxation is promoted through the micro-plastic state during material grinding instead of forced vibration in the cold state, and the welding seam cracking risk is greatly reduced.

The invention provides a multi-source dynamic disturbance rockburst combined support prevention and control system and method, and relates to the technical field of rockburst disaster prevention and control, the system comprises stress release holes, wave-absorbing grouting holes, energy-absorbing anchor rods and a passive pressure-bearing structure; the stress release holes are formed in a rockburst high-risk area of the tunnel surrounding rock; the wave-absorbing grouting holes are distributed around the rockburst high-risk area in a staggered mode, the wave-absorbing grouting holes are filled with wave-absorbing grouting materials, and a three-dimensional wave-absorbing grouting area is formed; the energy-absorbing anchor rod is arranged in the three-dimensional wave-absorbing grouting area; the passive pressure-bearing structure comprises a quick-setting concrete layer, a concrete layer containing rubber particles, a steel arch and a steel fiber concrete layer, the concrete layer containing rubber particles is arranged behind the reinforcing mesh, the steel arch is arranged behind the concrete layer containing rubber particles, and steel fiber concrete is arranged behind the steel arch. By constructing the pressure relief-wave absorption-energy absorption-passive pressure bearing four-stage combined supporting system, the safety and adaptability of the supporting system for the rockburst high-risk area are remarkably improved.

The invention relates to the technical field of titanium alloy pipe manufacturing, and particularly discloses a preparation method of a titanium alloy thin-walled pipe with superplasticity, comprising the following steps: S110, annealing a titanium alloy bar below a phase transformation point in a vacuum annealing furnace; s120, the annealed bar material is subjected to reciprocating extrusion treatment; s130, the bar subjected to reciprocating extrusion treatment is subjected to forward extrusion to form a pipe blank; s140, the pipe blank is subjected to superplastic bulging treatment; s150, after superplastic bulging is finished, heat preservation is stopped, and inert shielding gas continues to be blown in for cooling to the room temperature; and S160, stress relief annealing is conducted on the thin-walled pipe obtained after superplastic bulging, and the titanium alloy finished pipe with superplasticity is obtained. According to the method, the plasticity of the titanium alloy pipe is remarkably improved through reciprocating extrusion and superplastic bulging, the deformability is improved, meanwhile, the grain size is regulated and controlled, and preparation of the high-performance and high-size-precision thin-wall pipe is achieved.

The invention provides a method for repairing photovoltaic aluminum profile H13 die steel through self-fluxing alloy powder. The method comprises the steps that (1) the self-fluxing alloy powder is prepared; (2) the H13 die steel to be repaired is subjected to surface cleaning and decontamination, annealing treatment and preheating; (3) adjusting parameters of an optical fiber laser cladding system, and feeding the self-fluxing alloy powder into a laser acting area of the optical fiber laser cladding system; in the laser scanning process, a laser beam heats a local area into molten alloy liquid; (4) the alloy liquid is conveyed to the surface of the H13 die steel to be repaired, and a laser beam and the alloy liquid interact to form a firm cladding layer; protective gas is introduced to help the self-fluxing alloy powder flow; (5) gradient cooling is conducted after stress relief annealing is conducted on the cladding layer, and a high-precision numerical control grinding machine is used for finishing and polishing; and repairing is completed. When the self-fluxing alloy powder is used for repairing the H13 die steel, the repairing quality can be improved, the performance of the repaired H13 die steel can be remarkably improved, the production cost is reduced, and the service life of the H13 die steel is prolonged.

The invention provides an intelligent temperature control method and system for relieving stress of a glass annealing kiln. The method comprises the following steps: transmitting acoustic surface waves through a distributed sonic sensor to collect stress propagation data in glass, decoupling coupling characteristics of sound velocity and temperature, extracting a relaxation time constant, and generating a stress relaxation rate; performing time difference cross-correlation analysis to construct a stress propagation three-dimensional gradient field, establishing an incidence relation between the relaxation rate and the gradient field, and constructing a mapping strategy of the temperature set value and the relaxation rate according to the incidence relation; generating a dynamic temperature adjusting parameter and converting the dynamic temperature adjusting parameter into a heater power control signal; and dynamically adjusting a stress data feature extraction rule to match a real-time stress state according to the relevance between the gradient field update frequency and the temperature adjustment rate. According to the application, dynamic mutual optimization of the annealing stress elimination efficiency and the kiln temperature setting precision is realized, the glass residual stress is reduced, and the hidden danger of plate explosion is eliminated.

The invention discloses an oxygen-enriched destressing crystal growth method and a crystal growth furnace, and relates to the technical field of crystal growth, and the oxygen-enriched destressing crystal growth method comprises the following steps: step 1, pre-treating a PMNT polycrystal material, and putting the pretreated PMNT polycrystal material into a crucible; 2, pre-flushing the growth furnace and creating an oxygen partial pressure environment; 3, raising the temperature in the growth furnace to melt and homogenize the PMNT polycrystal material in the crucible; step 4, the crucible moves downwards for directional solidification of the crystal, a solid-liquid interface is formed and stably moves upwards, and in the process, a dynamic regulation and control strategy is adopted in the growth furnace to control an oxygen-enriched environment to promote crystal growth, so that the crystal digests growth stress in the growth process, and formation of oxygen vacancies is inhibited; and step 5, after crystal growth is finished, gradient cooling is performed to room temperature in an oxygen-enriched environment, and a crystal ingot is obtained. Oxygen is used as a regulation and control tool, the stress problem caused by oxygen vacancy is physically solved, the color center and performance problems caused by oxygen vacancy are chemically solved, and the crystal growth quality is improved.

Provided is an efficient preparation method of a bimetallic seamless composite pipe, and belongs to the technical field of steel pipe manufacture. The efficient preparation method of the bimetallic seamless composite pipe includes following steps: sheathing a base pipe blank on a cladding pipe blank to obtain a composite pipe blank, and carrying out a stress relief annealing treatment on the composite pipe blank, where the base pipe blank and the cladding pipe blank are made of different materials; heating the composite pipe blank after the stress relief annealing treatment to a hot working window temperature, and sheathing on a core rod of an extrusion cylinder after an insulation treatment, and then extruding along an axial direction of the extrusion cylinder to obtain a bimetallic seamless composite pipe.

The invention relates to the technical field of research and development of low-temperature bolt steel, and discloses a low-temperature impact performance control process for low-temperature bolt steel. Comprising the steps that S1, in the steelmaking refining stage, purity and uniformity control is conducted, S2, casting blank homogenization treatment is conducted, stress relief and structure regulation are conducted, S3, a heat treatment core process is conducted, structure and toughness balance regulation is conducted, and S4, online detection and dynamic feedback are conducted, and performance stability is guaranteed. By accurately controlling the element proportion of carbon (C), silicon (Si), manganese (Mn), chromium (Cr) and molybdenum (Mo) in steel and combining with an optimized heat treatment process (such as 860 DEG C oil quenching and 640-650 DEG C high-temperature tempering, and the heat preservation time is prolonged to 120 minutes or more), the V-shaped notch impact energy of the material in the environment of-101 DEG C stably reaches 35 J or more, the impact energy of part of samples can reach 50 J or more, and the impact energy of the part of samples can reach 50 J or more. The problem that the low-temperature impact performance is insufficient after wire hardening and tempering is thoroughly solved, and it is ensured that the brittle failure resistance of the bolt is remarkably improved in the ultralow-temperature environment.

The invention relates to the technical field of cladding welding of mining cutting picks, and discloses a method for high-entropy alloy laser cladding welding of mining cutting picks, which comprises the following steps: S1, surface decontamination: cleaning hard alloy of the mining cutting picks and the inner and outer surfaces of a steel base body seat; s2, raw material preparation is conducted, specifically, Ni-Cr-B-Si self-fluxing alloy powder, Cr elementary substance powder, Cu elementary substance powder and Ti elementary substance powder are mixed through a ball mill, and CrCuFeNiTi high-entropy alloy raw powder is formed; s3, welding is conducted, specifically, raw materials of the laser cladding layer are synchronously fed to the connecting position between the cutting pick hard alloy and the steel base body base, the raw materials of the laser cladding layer are melted through high-energy laser beam irradiation, and a CrCuFeNiTi high-entropy alloy laser cladding layer welding joint is formed; and S4, destressing is conducted, specifically, the laser cladding welding joint is subjected to oil immersion quenching and ultrasonic destressing, and the mining cutting pick is obtained. According to the method, the welding process can be controlled, heat damage to the steel base body seat and the hard alloy is avoided, the welding efficiency is high, and effective chemical metallurgical bonding of the hard alloy and the steel base body of the cutting pick can be achieved.

The invention relates to a 1100MPa-grade high-strength carbon tool steel wire rod and a manufacturing method thereof, a carbon component design is adopted, the rolled and spun wire rod is subjected to online molten salt isothermal toughening treatment, and the wire rod is controlled to enter a sorbite phase region from a high-temperature austenite state at a cooling speed of more than or equal to 32 DEG C / s to form a structure mainly comprising fine lamellar spacing sorbite; the steel wire rod is controlled to be subjected to isothermal tempering, sorbite lamellar fusing promotion and toughening destressing treatment in an isothermal interval, and finally the steel wire rod with the microscopic structure comprising tempered sorbite, ferrite and fused sorbite is manufactured through roller way slow cooling, so that the material cost can be reduced, the overall strength and plasticity of the steel wire rod can be improved, the tensile strength is 1020-1070 MPa, the percentage reduction of area is 46%-51%, and the steel wire rod can be manufactured into the steel wire rod with the microstructure comprising tempered sorbite, ferrite and fused sorbite. Therefore, the tool part can be directly machined after cold machining, additional heat treatment after cold machining is omitted, the production cost and energy consumption of downstream users are reduced, and the production efficiency and the yield are improved.

The invention discloses an efficient welding method for an exhaust silencer of a motorcycle. According to the invention, breakthrough improvement of manufacturing quality and efficiency is realized through multi-dimensional technical innovation. A high-frequency electromagnetic field resonance stress relief technology is creatively introduced, the metal crystallization behavior is intervened in real time in the welding process, and the thermodynamic equilibrium state of traditional welding is fundamentally reconstructed. Electromagnetic energy directly acts on molten metal in a microscopic particle vibration mode, lattice defects are promoted to be spontaneously repaired in the liquid stage, the deformation cracking risk caused by thermal stress accumulation in a traditional technology is avoided, and microstructure optimization is more synchronously completed. According to the dynamic energy field regulation and control means, the welding strength and toughness of the complex curved surface structure of the silencer are synergistically enhanced, a uniform and compact fine grain structure is formed in a welding seam area, the anti-fatigue performance of a product under the impact of high-temperature tail gas is remarkably improved, meanwhile, the necessary annealing procedure after traditional welding is integrated into in-situ treatment, and the production efficiency is improved. And the production period is greatly shortened.