336 results about "Embrittlement" patented technology

The invention discloses a 1000MPa-grade steel plate with high toughness, strain aging embrittlement resistance and excellent weldability and a manufacturing method thereof. The 1000MPa-grade steel plate comprises the following components in percentage by weight: 0.09 to 0.13 percent of C, less than or equal to 0.20 percent of Si, 0.70 to 1.00 percent of Mn, less than or equal to 0.013 percent of P, less than or equal to 0.0030 percent of S, 0.15 to 0.40 percent of Cu, 1.50 to 3.00 percent of Ni, 0.45 to 0.70 percent of Cr, 0.40 to 0.65 percent of Mo, 0.040 to 0.070 percent of V, 0.010 to 0.030 percent of Nb, 0.004 to 0.012 percent of Ti, 0.040 to 0.070 percent of Als, 0.0009 to 0.0017 percent of B, less than or equal to 0.0050 percent of N, less than or equal to 0.0030 percent The tensile strength of the steel plate is larger than or equal to 950 MPa, the yield strength is larger than or equal to 890 MPa, the Charpy longitudinal / transverse impact energy (single value) at the temperature of-60 DEG C is larger than or equal to 100 J, the strain aging transverse impact energy (single value) at the temperature of-40 DEG C is larger than or equal to 47 J, the elongation at break delta 5 is larger than or equal to 15%, and the weldability is good (the preheating temperature is smaller than or equal to 150 DEG C, and the steel plate can bear welding heat input of 30 kJ / cm-50 kJ / cm). And the method is particularly suitable for hydropower engineering, ocean platform structures and major equipment manufacturing.

The invention relates to the technical field of cable sheath materials, and provides a high-speed locomotive cable super-cold-resistant sheath material and a preparation method thereof, and the super-cold-resistant sheath material comprises the following raw material components by mass: 60-80 parts of a matrix polymer; 5 to 15 parts of a toughening agent; 3-10 parts of a cold-resistant auxiliary agent; 10 to 20 parts of a flame retardant; 1-5 parts of an antioxidant; 3-10 parts of a nano modified filler; and 1-5 parts of a cross-linking agent. The preparation method comprises the following steps: selecting the raw materials according to the proportion, putting the raw materials into mixing equipment, uniformly mixing to form a primary mixture, and preparing the primary mixture into the composite material through a melt blending process under specific temperature and shearing conditions. The obtained composite material is processed through an extrusion molding process to obtain a sheath material with excellent flexibility, impact resistance and aging resistance, and the problem that an existing material still has embrittlement, cracking or performance reduction in an extremely cold environment is solved.

The invention discloses a coating and hot-pressing process of a PHA material, and belongs to the field of packaging material coating. The process comprises the following steps: tightly combining a molten PHA coating material with a base material through hot pressing; the PHA coating is further compacted through a hot press polish roller, and bubbles between the PHA coating and the base material are eliminated; then entering a cooling device, rapidly cooling through internal water circulation so as to cure the PHA coating, and meanwhile, spraying a trace amount of deionized water mist so as to prevent the base material from being dried and embrittled due to high temperature; entering a recrystallization zone, regulating and controlling the crystallinity of PHA, and balancing the mechanical property and degradation rate. The PHA can be well bonded with various base materials (such as paper, fabrics and films) in the hot pressing process, and an additional adhesive is not needed. Therefore, the technological process is simplified, and the cost is reduced. And the PHA can be uniformly coated on the surface of the base material through the hot pressing process to form a compact coating, so that the performance consistency of the product is ensured.

The invention discloses an austenitic stainless steel welding wire for a liquid hydrogen storage tank and a preparation method and application of the austenitic stainless steel welding wire, and belongs to the technical field of welding materials and preparation of the welding materials. The welding wire solves the problem that the low-temperature performance of a welding seam is poor when the current welding wire for the liquid hydrogen storage tank is used for welding. The welding wire comprises the following chemical components in percentage by mass: less than or equal to 0.02% of C, 0.4-1.5% of Si, 5.0-7.5% of Mn, less than or equal to 0.020% of S, less than or equal to 0.030% of P, 16.0-22.0% of Cr, 15.0-18.0% of Ni, 2.0-5.0% of Mo, 0.05-0.2% of N, less than or equal to 0.01% of O and the balance of Fe and inevitable impurities. According to the welding wire, deposited metal is low in low-temperature embrittlement tendency, high in low-temperature strength and excellent in low-temperature impact and fracture toughness. The welding wire is used for welding the austenitic stainless steel liquid hydrogen storage tank and is wide in application range, and the mechanical property of deposited metal is good.

The invention relates to the technical field of cables, in particular to a preparation method of a high-temperature-resistant low-temperature-resistant high-toughness cable material and a cable for an oil platform, the cable comprises a cable body, a bionic stranded conductor is arranged in the cable body, and a gradient insulating layer is fixedly connected to the surface of the bionic stranded conductor. The surface of the gradient insulation layer is fixedly connected with a three-layer co-extrusion sheath layer. According to the invention, the feasibility of a core innovation point (a bionic conductor and a gradient sheath) is proved through basic performance verification, the typical working conditions of an oil platform, such as low-temperature embrittlement and dynamic load, are covered through an extreme environment test, and the synergistic effect of key parameters (DCP dosage and vulcanization temperature) is determined through technological parameter optimization; the relation between quantitative repair efficiency and trigger conditions is verified through a self-repair mechanism, three-year equivalent aging is simulated through long-term reliability evaluation, the technical economy is proved, and meanwhile the core requirements of wide-temperature-range stability, mechanical fatigue resistance, chemical corrosion resistance and the like are met.

To suppress embrittlement of a powder line part material by production of zirconium carbide inside a powder line part, and occurrence of sudden troubles such as hole opening of the powder line part caused by the embrittlement.SOLUTION: A molten steel flow passage 5 includes an upstream flow part 50 provided with an inflow port 3, a downstream flow part 52 provided with a discharge hole 4, and a boundary part 51 in a boundary between the upstream flow part 50 and the downstream flow part 52, wherein a circle equivalent diameter DU of the upstream flow part 50 is set to be larger than a circle equivalent diameter DL of the downstream flow part 52, the boundary part 51 is provided at a position higher than the powder line part 6, and a lining layer 7, which is composed of a material different from a zirconia / graphite material and has thickness of 8 mm or more, is provided inside the power line part 6.SELECTED DRAWING: Figure 1

The invention relates to the technical field of waste battery recycling, in particular to a battery module lossless disassembling method based on low-temperature brittleness difference, which comprises the following steps: step 1, analyzing material brittleness and formulating a gradient cooling program; 2, local directional cooling and embrittlement control, wherein a low-temperature cooling medium is adopted to conduct directional spraying on the adhesive concentration area, and meanwhile the temperature of the metal current collector is maintained to be higher than the embrittlement temperature of the metal current collector through heat insulation protection; temperature distribution is monitored in real time, cooling parameters are dynamically adjusted, and it is ensured that a target material is completely embrittled; step 3, vibration separation and layered recovery: applying low-frequency vibration to the embrittled battery module to break the embrittled material layer; and sorting materials based on fragment size and density difference, and recovering the complete metal current collector. By means of the steps, it is guaranteed that materials are not damaged in the disassembling process, and lossless disassembling and efficient recycling of the battery module are achieved through accurate control and the efficient sorting process.

The invention discloses an anti-embrittlement flexible armored cable in an extremely cold environment. The anti-embrittlement flexible armored cable comprises a conductor, an insulating layer, a buffer isolation layer, a flexible armored layer and an outer sheath layer which are sequentially arranged from inside to outside. According to the armored cable, the structure of an existing cable is improved, the material formula of the insulating layer and the material formula of the outer sheath layer are optimized, the requirements for embrittlement resistance and high flexibility can be met, the protection performance of the armored cable can be enhanced, and aging tests show that the cable has good flexibility. The cable can meet the use requirement of long-term stable operation under the extremely cold severe condition with the temperature of-60 DEG C, has important practical significance and economic value, is reasonable in design, and is worthy of popularization and use.

The invention relates to the technical field of electric digital data processing, in particular to an aging analysis method for a boiler dissimilar steel welded joint, and the method comprises the following steps: carrying out a performance test on the prepared dissimilar steel welded joint to obtain a performance test result; based on a performance test result, obtaining a first aging degree grading database corresponding to the nonlinear ultrasonic coefficient and the different aging degree data, and a second aging degree grading database corresponding to the magnetic characteristic parameter and the different aging degree data; and utilizing the first aging degree grading database and the second aging degree grading database to construct an aging degree grading database of the prepared dissimilar steel welding joint under different aging degrees. Therefore, the problems that in the related technology, component embrittlement, carbon migration, creep strength mismatch, residual stress concentration and the like of a fusion area are prone to occurring, safe operation of a unit is seriously threatened, and a dissimilar steel welding joint is high in non-uniformity, prone to cracking and the like are solved.

The invention relates to the technical field of building materials, and discloses a self-repairing microcapsule-based composite waterproof material and a preparation method thereof, and the self-repairing microcapsule-based composite waterproof material comprises the following components by weight: 60-80 parts of modified organic silicon resin, 5-15 parts of nano clay (modified montmorillonite), 3-8 parts of a self-repairing microcapsule, 2-5 parts of a water-based cross-linking agent, and 0.5-2 parts of a dispersing aid. Stress generated by settlement and temperature change of a building structure can be effectively resisted, and cracks are reduced fundamentally; meanwhile, the material still keeps flexibility at the low temperature of-30 DEG C (without cracks when bent), and the technical bottleneck that a traditional material is prone to embrittlement in a cold region is broken through; more importantly, the 24-hour self-repairing rate is up to 92%, self-healing of cracks can be achieved without manual intervention, the service life of waterproof engineering is prolonged to more than two times that of a traditional material, the full-life-cycle maintenance cost is remarkably reduced, and a long-acting and reliable solution is provided for the field of building waterproofing.

The invention relates to the technical field of photovoltaic connector manufacturing, in particular to a temperature control forming process of a photovoltaic nylon connector mold and a composite runner, the mold is divided into a fixed mold area, a movable mold area, a mold cavity area, a mold core area and a pouring gate area, and each area is provided with an independent temperature control loop. According to different requirements of the mold filling state and the cooling stage of nylon materials, the temperature of each area of the mold is dynamically adjusted, the mold temperature is properly increased in the initial mold filling stage, a cavity is rapidly filled with melt, and along with mold filling, the mold temperature is gradually reduced, and melt cooling and crystallization are accelerated. According to the temperature control forming process of the photovoltaic nylon connector mold and the composite runner, the phase change energy storage material is embedded in the fixed mold area of the mold, and the heat absorption and release characteristics of the phase change energy storage material during phase change are used for assisting temperature control, so that the problem of embrittlement or insufficient strength caused by non-uniform crystallization of a product in a traditional process is solved; and the photovoltaic connector is ensured to have good mechanical property and weather resistance in long-term use.

The invention relates to a method for evaluating the crack initiation probability of an RPV surface crack under a transient working condition, and belongs to the field of safety analysis of nuclear pressure-bearing equipment. The method comprises the following steps: sampling a random variable and determining a sampled multivariate sample; calculating a stress intensity factor of the crack evaluation point caused by multiple loads under the transient condition; calculating a stress intensity factor of the crack evaluation point after the influence of the crack tip plastic zone is brought into the transient condition; calculating the reference temperature of the crack evaluation point after neutron irradiation embrittlement is considered under the transient condition; constructing a fracture toughness probability distribution model of the crack evaluation points under the transient condition; calculating the crack initiation probability of the crack at the current moment under the transient condition; judging whether the current moment is the last moment of the transient working condition, if so, ending the calculation process of the crack initiation probability under the transient working condition, and otherwise, updating the transient moment; and evaluating the crack initiation probability of the RPV surface cracks under all samples. According to the method, the crack initiation probability of the RPV surface crack under the transient working condition can be efficiently and accurately evaluated.

The invention relates to the technical field of laser welding, and particularly discloses laser welding equipment for instrument and meter production and manufacturing, the laser welding equipment for instrument and meter production and manufacturing achieves the purpose of stably clamping a circular workpiece, and the equipment is supported by an equipment bottom plate and an equipment bracket; the welding support supports the electric lifting table and the laser welding head, the laser welding head welds components, the protection device performs gas protection on the components, gas consumption is low while gas protection is performed in the welding process, and the density of pure inert gas is slightly larger than that of air, so that gas retention is facilitated, and the welding quality is improved. According to the welding device, the circular shell accessories are fixed and rotated through the corresponding assemblies, so that the welding requirements of different angles are met, meanwhile, liquid inert gas is gasified and heated through the pneumatic device, welding embrittlement caused by gas supercooling is avoided, and the error influence caused by fan vibration on welding is counteracted.

The invention relates to the technical field of welding equipment, and particularly discloses cooling equipment for metal building material welding, and the cooling equipment for metal building material welding achieves the purposes of cooling a workpiece and carrying out gas protection during welding. The heat dissipation device dissipates heat generated in the welding device, so that the working state of the welding device is stabilized, long-time work is facilitated, gas is guided into the surface of a workpiece through the pipeline design of the heat dissipation device, and therefore the welded workpiece is rapidly cooled; due to the fact that the temperature rises after heat is transferred through the surface of the welding device, the temperature difference between the gas temperature and the workpiece is reduced, workpiece embrittlement caused by too fast cooling is avoided, the heat dissipation device blows the surface of the workpiece in a targeted mode, compared with a traditional gas protection mode, the using amount of nitrogen is reduced, the workpiece is self-locked and fixed through the fixing device, and the welding efficiency is improved. And welding errors caused by shaking of the workpiece during welding are prevented.

The invention discloses a method for improving the welding performance of low-alloy high-strength wind power steel, which is characterized by comprising the steps of optimization of welding heat input, preheating before welding, welding process control and slow cooling after welding. By optimizing the welding heat input parameters, reasonably controlling the time (t8 / 5) for cooling to 500 DEG C from 800 DEG C, adjusting the structure transformation behavior of the welding heat affected zone and combining the process measures of preheating before welding, slow cooling after welding and the like, precise regulation and control of the microstructure of the welding heat affected zone are achieved, the hardening tendency and the embrittlement phenomenon of a coarse grain zone are effectively restrained, and the welding quality is improved. And therefore, the strength, toughness and crack resistance of a welding joint are remarkably improved, and the high requirements of offshore wind power structural parts for welding quality and service performance are met.

The invention belongs to the field of natural gas development, and discloses a high-strength and high-ductility soluble alloy and a preparation method and application thereof, and the soluble alloy comprises the following components in percentage by weight: 8-10% of Mg, 1-2% of Ce, 0.5-1% of Mn, 0.1-0.5% of Bi, 1-2% of Re, 0.5-1% of Ti, 0.5-1% of C, 0.5-1% of Cr, 0.5-1% of Ga, 0.5-1% of Cu and the balance of Al and impurities. The strengthening effect of the Mg element on the aluminum alloy is improved by increasing the content of the Mg element in the alloy, meanwhile, the problems of low tensile strength and sodium brittleness caused by the high Mg element content are solved, the prepared soluble alloy has the characteristics of high strength, high ductility and good solubility, and the performance requirements of the bridge plug preparation field on the soluble alloy are met.

The utility model provides a dissimilar steel strip isolating layer submerged-arc welding structure which comprises a first base material and a second base material, the edges of the first base material and the second base material are subjected to the same beveling operation, specifically, the front side and the back side of each plate end are each provided with a beveled edge, the plate ends are assembled to form an X-shaped beveled edge, and a truncated edge is reserved in the middle of each beveled edge; and surfacing the edge of the first base material to form a first welding body with the same thickness, butting the edges of the first base material and the second base material, and welding to obtain a second welding body. According to the method, subsequent submerged-arc welding is converted into similar steel welding through the isolation layer structure, and the risk of cracking caused by interaction of high residual stress and brittle structures after dissimilar steel welding is eliminated; and meanwhile, the problems that a wide recarburization and decarburization layer is generated due to carbon diffusion migration in direct welding of dissimilar steel, and cracking is caused due to serious ferrite embrittlement of a decarburized wide ferrite belt under long-time heat treatment and high-temperature operation are solved.

The utility model relates to the technical field of turnover boxes, in particular to a low-temperature-resistant turnover box with a lateral outwards-protruding guide sliding structure, which comprises a turnover box main body and a sliding mechanism. According to the turnover box, through the arrangement of an anti-skid pad, an anti-skid block, a sliding groove, a first sliding block, a buckle and a clamping groove, firstly, the box cover is opened, the box cover is pushed to be closed after objects are put in, a first insertion buckle on one side of the lower portion of the box cover is inserted into an insertion buckle groove in one side of the top of the turnover box body to be fixed, and secondly, a protection mechanism in the turnover box body can buffer external impact force and vibration; the low-temperature-resistant coating prevents the main body from being embrittled and broken, and the insulation board maintains the low-temperature environment in the box and protects the quality safety of articles. And finally, the bottom non-slip mat increases friction force to ensure the stability of the turnover box, and the non-slip blocks on the two sides assist in guiding and prevent sideslip during transportation. When a plurality of turnover boxes are connected, the first sliding blocks are inserted into the sliding grooves, the buckles and the clamping grooves are clamped to guarantee firm connection, and the first sliding blocks can be pulled out by pressing down the buckles during separation.

The invention belongs to the field of organic silicon materials, and particularly relates to carborane modified heat-resistant silicone oil and a preparation method thereof. The carborane modified heat-resistant silicone oil is prepared by introducing a molecular chain containing a benzene ring and carborane structure into a side chain of the silicone oil, and the heat resistance and radiation resistance of the hydrogen-containing silicone oil are remarkably improved by utilizing the synergistic effect of a cage structure of the benzene ring and carborane; the modified silicone oil can still keep good physical and chemical properties in high-temperature and radiation environments, the application range of the modified silicone oil in the high-temperature and radiation fields is expanded, the modified silicone oil rubber material containing a carborane structure can be further processed to be used in a thermal protection system of an aircraft, and the situation that the aircraft is prone to falling off in the high-speed flight process is prevented. And the material embrittlement and cracking are caused by violent friction between the surface of the aircraft body and air, so that the structural integrity of the aircraft is effectively protected.

The invention relates to the technical field of steel-plastic composite pipe machining, and discloses a steel-plastic composite pipe sealing forming device and method.The steel-plastic composite pipe sealing forming device comprises a base, a supporting mechanism, a sealing mechanism, a grinding mechanism and a fixing plate are arranged at the top of the base, and a rotating shaft is rotationally installed in the fixing plate; the sealing mechanism comprises an extrusion cylinder and a spiral auger, the spiral auger is rotatably mounted in the extrusion cylinder, one end of the extrusion cylinder is communicated with a square-opening extrusion nozzle, and a preheating mechanism and a flattening mechanism are arranged on one side of the extrusion cylinder. The device is reasonable in design, the temperature of a plastic layer and the contact pressure of the flattening roller are monitored in real time through a closed-loop control system integrating the temperature sensor, the pressure sensor and the semiconductor refrigeration ring, the temperature sensor dynamically adjusts the power of the semiconductor refrigeration ring, and the cooling airflow temperature is accurately controlled; embrittlement caused by too fast cooling of the plastic layer or deformation caused by insufficient cooling is prevented.

Disclosed in the present invention is a composite coating for steel. The composite coating comprises a first coating and a second coating which are sequentially arranged in the thickness direction of the coating, wherein the first coating is in direct contact with a steel substrate and comprises Mo and / or Cr, and the second coating is a zinc-based coating. Further disclosed in the present invention are a coating method for the composite coating, a steel plate comprising the coating, and a spot-welded joint comprising the steel plate. The present invention can greatly inhibit the phenomenon of liquid metal embrittlement caused by welding during a spot welding process, reduce cracks generated due to the phenomenon, and ensure the performance stability and functional stability of a steel plate, especially a galvanized high-strength steel plate.

This invention provides a crack-resistant, high-toughness composite packaging bag and its preparation method, relating to the field of composite packaging bag technology. The bag includes a bag body comprising an inner cold-resistant toughening layer, a middle elastic buffer layer, and an outer tough protective layer. The inner wall of the bag body has a material guide strip, and the bottom of the inner wall has longitudinal reinforcing ribs. The material guide strip has exhaust micropores. A flexible buffer pad is installed at the bottom of the bag body. Elastic buffer strips are provided on both sides of the bag body. Rounded transition corners are provided on both outer sides of the bottom of the bag body. In this invention, by using an inner cold-resistant toughening layer made of modified metallocene PE and POE toughening agents combined with a TPE material middle elastic buffer layer, the toughness of the bag body in low-temperature environments of -18℃ to -5℃ is significantly improved, preventing low-temperature embrittlement of the substrate. It can effectively withstand the instantaneous impact of high-speed filling of viscous materials, completely solving the problem of low-temperature embrittlement and cracking.

This invention relates to the field of alloy materials and discloses a method for preparing copper-chromium alloys by recycling copper-chromium alloy waste, comprising: 1) degreasing: immersing the copper-chromium alloy waste in an organic solvent to remove oil, cleaning, and drying; 2) embrittlement: placing the copper-chromium alloy waste in a hydrogen atmosphere, heating to above 500°C for at least 1 hour to embrittle, and then cooling; 3) cryogenic crushing: ball milling the copper-chromium alloy waste in liquid nitrogen medium to obtain copper-chromium alloy powder; 4) molding and pre-sintering: molding and pre-sintering the copper-chromium alloy powder to obtain a sintered blank; 5) densification: densifying and sintering the sintered blank to obtain a copper-chromium alloy. This invention sequentially processes copper-chromium alloy waste through degreasing, embrittlement, cryogenic crushing, molding and pre-sintering, and densification to obtain a copper-chromium alloy with high purity, high electrical conductivity, and high strength, achieving efficient recycling and reuse of copper-chromium alloy waste.

The invention belongs to the field of polymer composite materials, and discloses an antistatic composite material for a safety helmet and a preparation method of the antistatic composite material. Comprising the following components: 70 to 90 parts of a PC / ABS blending matrix, 12 to 20 parts of basalt fiber treated by a titanate coupling agent NDZ-311, 4 to 8 parts of a graphene quantum dot modified carbon nanotube-polyethylene glycol composite antistatic agent, 3 to 6 parts of polyaryletherketone micro powder, 0.2 to 0.6 part of an antioxidant 1010 and 0.4 to 1.0 part of calcium stearate. Wherein the mass ratio of PC to ABS in the PC / ABS blended matrix is (6: 4)-(7: 3); the invention aims to solve the problems that in the prior art, a single antistatic agent is difficult to consider the antistatic effect and the mechanical property, or materials are embrittled due to high addition amount, or the antistatic property fluctuates along with the environment and is easy to lose due to low addition amount; the interface bonding force between the conventional reinforced fiber and the PC / ABS matrix is weak, and the mechanical strength is limited to be improved; the long-term aging resistance of the material is poor, and the long-term use requirements of outdoor, chemical and other severe environments cannot be met.

The invention discloses a steel plate for a low-temperature storage tank of a liquefied gas carrier and a manufacturing method of the steel plate. The steel plate comprises the following chemical components in percentage by weight: less than or equal to 0.019% of C, less than or equal to 0.09% of Si, 2.50-3.50% of Mn, less than or equal to 0.009% of P, less than or equal to 0.005% of S, 5.00-6.00% of Ni, 0.010-0.035% of Al, less than or equal to 0.006% of N, 0.0009-0.0015% of B and the balance of Fe and other inevitable impurities. A 5.5 Ni-medium Mn-(Mo)-B component system is adopted for the steel plate, a special heat treatment process of one-time tempering and two-time quenching is combined, Mn and Ni are matched to play a role in stabilizing retained austenite and inverted austenite, the concentration gradient of a grain boundary or phase boundary manganese element is remarkably reduced, the stress concentration of the phase boundary and the number of crack sources during follow-up impact deformation are reduced, and the quality of the steel plate is improved. The manganese brittleness phenomenon is improved, the impact toughness of the low-temperature steel plate is remarkably improved, and therefore the low-temperature impact toughness of the steel plate at the temperature of-196 DEG C is guaranteed.

A wrought nickel-molybdenum alloy containing 27.22 wt.% molybdenum, 4.73 wt.% iron, 0.47 wt.% chromium, 0.67 wt.% manganese, and 0.25 wt.% aluminum, and the balance nickel, as well as this alloy plus or minus the manufacturing variances typically encountered by each element during air melting, vacuum melting, and electro-slag remelting, have improved resistance to thermally-induced embrittlement over 100 hours at 1200⁰ F.

This invention discloses a method for improving the low-temperature impact toughness of high-strength heat-treated steel rails, comprising the following steps: composition control, smelting and refining, rare earth modification treatment, continuous casting / billing and heating homogenization, two-stage controlled rolling forming, online heat treatment with graded cooling and residual heat recovery, slow cooling on a cooling bed and straightening finishing. This invention determines the composition window based on the common constraint range of two sets of steel chemical composition standards for rails, and through the synergistic control of purification, effective rare earth modification, two-stage controlled rolling for grain refinement, and the online graded cooling and residual heat recovery heat treatment path, it reduces the sensitivity to low-temperature crack initiation, constrains the phase transformation path, and weakens the coupling between residual stress and microstructure embrittlement. Thus, while meeting the requirements for high strength, hardness, and wear resistance, it achieves qualified and stable low-temperature impact toughness.

To reduce, when producing a high-tensile-strength steel wire using a straight-type continuous wire-drawing machine, strain age hardening (embrittlement) caused by temperature rise of the steel wire, support high-speed wire drawing, and improve line set.SOLUTION: In wire drawing, at least in the drawing passes other than the final pass, a hole die or a roller die is used, and the cross-sectional shape of a workpiece material at a die exit is formed not as a circle but as an elliptical shape having a straight portion or as a rounded rectangular shape. By winding and taking up the workpiece material with the straight portion thereof in contact with a drawing capstan, rolling (twisting) of the workpiece material is restrained, and contact cooling by the drawing capstan is enhanced, thereby suppressing age hardening. The action of back tension also reduces processing heat generation. The restraint of twisting improves line set.SELECTED DRAWING: Figure 1

The invention discloses a low-polarity hot-melt pressure-sensitive adhesive, which is prepared from the following raw materials in percentage by weight: 50 to 70 percent of APAO polyolefin, 10 to 25 percent of alkane wax, 20 to 30 percent of petroleum resin and 0.1 to 1 percent of antioxidant. The APAO polyolefin with different melt viscosities and different molecular weights at 90 DEG C is adopted, so that the cohesion, flexibility and thermal stability of the colloid can be remarkably improved, and the problem of high-temperature flowing or low-temperature embrittlement generated by the APAO polyolefin with single performance is avoided. According to the invention, the balance between the low viscosity of 3000 + / -300cps at 150 DEG C and the high softening point of more than or equal to 120 DEG C is realized. And moreover, the quick opening time and the wide temperature range adaptability are considered, and the film covering performance of plastic films such as BOPP, PET and PE is improved.

The invention discloses a laser and electric arc hybrid welding method and a T-shaped structure, and the laser and electric arc hybrid welding method comprises the steps that a coating is arranged on one side of a first base material; abutting the end part of one end of the second base material against the coating layer; and welding the two sides of the second base material in the thickness direction to the coating. The coating is arranged on one side of the first base material before the first base material and the second base material are welded, and the coating can reduce the overall hardness of the joint of the first base material and the second base material, so that the risk of interface embrittlement of the joint of the first base material and the second base material in the welding process is reduced; and the ductility of the joint of the first base material and the second base material can be improved, so that the stress can be better dispersed when the joint is subjected to external force, and the risk of brittle fracture of the joint is reduced.