82results about How to "Avoid Surface Quality Issues" patented technology

The invention discloses a method for preparing seamless steel tubes made of martensite precipitation hardening stainless steel, which comprises the following steps of billets, peeling, blanking, heating, hot punching, cooling, finishing, acid cleaning, lubricating, degreasing, heat treatment, straightening, tube cutting, acid cleaning, inspection, and packaging and warehousing. Compared with the prior art, the method has the following advantages that: pierced billets after hot punching are cooled in a pile so as to reduce working procedures and cost; the intermediate heat treatment adopts solution treatment, has short time and high efficiency, and improves surface quality; the tubes all adopt cold rolling process to improve yield; and vacuum aging treatment is adopted to improve the comprehensive mechanical property, the finished product inspection qualified rate reach 95 percent, and the yield from the billets to the finished products reach 51.31 percent.

The invention discloses a method and device for manufacturing efficient and high-precision composite additive, and the method and device are achieved through composition of a laser beam and an electron beam. In the process of the action of a high energy beam and metal powder, metal powder of a surface outline is scanned and molten through the laser beam, and the surface of a part has a good surface quality. The electron beam melts the internal powder at a high speed to form a part inner cavity so as to reach the highest forming efficiency. The lower portion of the device comprises a powder laying roller, a workbench, a powder conveying cylinder and a working cylinder. The upper portion of the device comprises an electron beam generating device, a laser beam generating device, a bottom plate, two guide rails, two beams, a synchronous belt wheel and a servo motor. The electron beam generating device and the laser beam generating device are respectively integral and move to the forming area alternately to carry out scanning. By means of the method and device, the defects in the single forming technology can be overcome, and the purposes of reasonably controlling the formed microstructural organization and optimizing the comprehensive performance are achieved.

The invention relates to the field of steel making, in particular to a method for reducing the residual stress of a steel rail, the steel rail obtained according to the method, and the application of the steel rail. The method for reducing the residual stress of the steel rail comprises the step of sequentially carrying out accelerated cooling, slow cooling and air cooling on the rail head tread centers, the two sides of each rail head and the center part of the rail base of the steel rail obtained after rolling, wherein the starting cooling temperature of accelerated cooling is 650 DEG C to 950 DEG C, the cooling rate of accelerated cooling is 2 DEG C per second to 8 DEG C per second, the finish cooling temperature of accelerated cooling is 400 DEG C to 600 DEG C, the cooling rate of slowing cooling is 0.1 DEG C per second to 1.5 DEG C per second, and the finish cooling temperature of slow cooling is 180 DEG C to 300 DEG C. With the method for reducing the residual stress of the steel rail, on the premise that the tensile property of the steel rail is guaranteed, the residual stress of the steel rail can be effectively reduced, and the flatness of the steel rail can be improved. The steel rail is particularly suitable for high-speed railways.

The invention discloses laser induced low pressure jet flow combined etching processing method and device thereof. The method comprises the following steps: the operations of cutting, drilling and slotting are performed on a workpiece by utilizing high-energy laser beams generated by a laser processing system, and meanwhile erosion is performed on the material surface subjected to laser ablation through high-speed jet flow beams generated by a corrosive medium jet flow device, so that the purpose of removing the material is achieved; the device comprises a laser device and a power source, and further comprises a jet flow generation device and a corrosion liquid circulating reflux device, wherein the jet flow device comprises a corrosion liquid tank, a plunger piston high pressure pump, a pressure gauge, an accumulator, a one-way control valve, a corrosion-resistant spray nozzle and a jet flow device fixed fixture. The method disclosed by the invention has the advantages that the laser ablation is mainly performed, the cooling of high-speed corrosive medium jet flow beams, synchronous erosion and combined processing effect of the cooling and the erosion are added on the basis of the laser ablation, so that the laser induced low pressure jet flow combined etching processing of the material is realized; the invention provides an efficient, clean and combined etching processing process.

The invention relates to a method for laser-assisted polishing of a CVD diamond. The method comprises the following steps: first, selecting a suitable laser type according to the material property ofthe CVD diamond, and simulating the laser ablation of the CVD diamond so as to acquire suitable laser ablation parameters; then, carrying out laser rough polishing based on optimum laser process parameters; and finally, carrying out mechanical precision polishing by the adoption of a polishing disc till the required precision is achieved, so that a graphitization layer generated during the laser ablation process and surface defects such as microcracks can be removed. Through the method provided by the invention, the problems that the graphitization layer is easy to generate during the laser polishing process of the CVD diamond and the polishing efficiency of the mechanical polishing process is low can be solved.

The invention discloses a manufacturing method of secondary-cold-rolling shadow mask strip steel in a thin specification. The manufacturing method comprises the following steps of: carrying out converter steelmaking; carrying out continuous billet casting; carrying out acid washing and cold rolling; preparing a machine set; carrying out continuous annealing; carrying out secondary cold-rolling; degreasing; and finishing and oiling. The mass percentage of each element is controlled in a corresponding range, wherein the mass percentage of C element is controlled to be less than or equal to 0.002%; the plate temperature is 685-705 DEG C and the soaking time lasts for 30-50 seconds in a heating section and a soaking section of the continuous annealing step; and the rolling reduction of secondary cold rolling is 20%-50%. By using the manufacturing method, a shadow mask strip steel product having ultra-low carbon, an thickness of less than or equal to 0.15 mm and better surface quality and use property can be obtained; as a secondary cold rolling process is adopted, the strength and the rigidity of an annealed product can be improved, decarburization and annealing steps can be omitted, the production flow can be shortened, the production cost can be reduced and the energy consumption and the waste discharge can be reduced.

The invention relates to a resetting device using flexible positioning and rigid clamping in combination and a positioning method thereof. The invention is characterized in that a cartridge comprises two to four radially-arranged positioning gears, the lateral side of each positioning gear is provided with a positioning slant surface, Z-direction stopping planes are arranged between two adjacent positioning gears, a workpiece supporting board is provided with positioning slots fit with the positioning gears and positioning planes fit with the Z-direction stopping planes, a pop-rivet comprises a pop-rivet body which is connected with the workpiece supporting board by bolts, the pop-rivet orifices on the cartridge is provided with positioning cone surfaces, the lateral side of the pop-rivet body is provided with cone-shaped positioning contact planes fit with the positioning cone surfaces. The device can simultaneously realize precise resetting and rigid clamping, and ensure high safety and reliability of mechanical processing and high manufacture preciseness and efficiency of the processed object.

The invention relates to abrasion-resistant steel good in surface quality. The abrasion-resistant steel comprises the components of 0.12-0.20% of C, 0-0.1% of Si, 0.6-1.20% of Mn, 0.010-0.040% of Nb,0-0.01% of V, 0.010-0.030% of Ti, 0-0.04% of Al, 0-0.1% of Ni, 0-0.1% of Cu, 0.10-0.40% of Cr, 0-0.1% of Mo, 0.001-0.005% of B, 0.0010-0.0050% of Ca, 0-0.010% of P, 0-0.0015% of S, 0-0.0012% of O, 0-0.0035% of N, 0-0.0002% of H and the balance Fe; and the carbon equivalent CEV is smaller than or equal to 0.4, and PCM is smaller than or equal to 0.25. The production technological process comprisesthe steps of converter steelmaking, LF refining, VD or RH high vacuum degassing, continuous casting, heating, rolling, shot blasting treatment, quenching and tempering. The abrasion-resistant steel has the better surface quality and is free of gas pits, inclusion, pockmarks, press-in scales and other surface defects. The depth of surface mottles caused by scale disengagement is smaller than or equal to 0.1 mm, and steel plate surface coping can be not conducted. Based on element design, preheating-free welding and excellent toughness can be further achieved.

The invention relates to a preparation method and application of 700 MPa grade ultra-fine grain high-strength weathering steel. The preparation method includes the steps that a continuous casting blank directly enters an M rack rough rolling unit at a high pulling speed and is subject to M-gate continuous high reduction (50%-60%) rough rolling, austenite grains are greatly refined, after rough rolling is carried out, an intermediate billet is quickly heated by an induction heating furnace to the temperature needed by a finish rolling inlet, and meanwhile a reverse temperature field is formed; and then the blank sequentially passes through a finish rolling unit, a laminar cooling part and a reeling machine, and the microstructure characteristics that the surfaces and core parts are thick and 1/4 thickness parts are thin are finally formed. In the production process, finish rolling and rough rolling are both full-endless rolling. By means of the preparation method, an ultra-fine grain high-strength weathering steel strip with the weather fastness equal to that of corten-A can be obtained, the effects of replacing thick parts with thin parts and replacing cold with heat are achieved, and the automotive body weight is small; and meanwhile, the service life of an automotive sheet is prolonged, the production efficiency is improved, the production cost is reduced, energy consumption is reduced, emission is reduced, and resource-saving and environment-friendly production is achieved. The preparation method and application belong to the technical field of metallurgy.

The invention discloses a method for recovering 99.98% copper powder from etching liquid and further processing the copper power to prepare 99.999% cathode copper. According to the method, firstly, the etching liquid is subjected to dialysis in an electrodialysis cell containing a copper sulphate solution, and copper ions in the etching liquid enter the copper sulphate solution, so that a high-concentration copper sulphate solution is obtained; then the high-concentration copper sulphate solution is introduced into an electrolytic cell for electrolysis, so that the high-purity copper powder isobtained; then the high-purity copper powder is pressed into a brick, the copper brick is placed in a conductive frame made from a titanium material, and is used as an anode, a pure titanium board isadopted as a cathode, and refining is conducted in the electrolytic cell so that the cathode copper with purity of 99.999% can be obtained at the cathode of the electrolytic cell. The method belongsto the field of ageing etching liquid for copper extraction, regeneration and reuse, and compared with a traditional technology, the method has the characters that added values of products are high, both the copper powder and the cathode copper can be used as products, moreover, a process is short, equipment is little, and energy consumption is low; moreover, in the whole process, no other agentsare introduced, no intermittent products are polluting, and the requirements of environmental-protection can be met.

The invention provides a groove grinding disc and a method for manufacturing the groove grinding disc. The grinding disc is provided with a groove; the groove is formed by coupling a plurality of concentric grooves with radii gradually increasing and a plurality of spiral line grooves which are arranged at equal intervals; the centers of the spiral line grooves are concentric with the centers of the concentric grooves; the grinding disc is divided into a first area, a second area and a third area from inside to outside in the radial direction; and the distance between the concentric grooves ofthe first area and the distance between the concentric grooves of the third area are greater than the distance between the concentric grooves of the second area. The application of the technical scheme can realize the improvement of the flow performance of grinding liquid in the grinding and polishing process, and the problems of blockage and wear of the grinding disc are obviously improved.

The invention relates to 780 MPa-grade hot-rolled dual-phase steel with excellent hole expanding performance. The 780 MPa-grade hot-rolled dual-phase steel comprises the following chemical components including, by weight: 0.05%-0.09% of C, 0.10%-0.30% of Si, 1.40%-1.60% of Mn, less than or equal to 0.010% of P, less than or equal to 0.003% of S, 0.08%-0.12% of Ti, 0.20%-0.24% of Mo, 0.010%-0.030% of Nb and 0.08%-0.12% of V. The production method comprises the following steps of carrying out vacuum treatment after converter smelting, heating a casting blank after continuous casting is conducted to form a blank, carrying out rough rolling, carrying out finish rolling, carrying out two-stage cooling and carrying out coiling. The grain size grade of ferrite and martensite is greater than or equal to 10 grades; the area ratio of the martensite is 30%-50%, a ferrite matrix contains a large number of nanoscale cluster precipitates, the size of the nanoscale cluster precipitates is 1-8 nm, and the density of the nanoscale cluster precipitates can reach 1*10<3>/microns<2>; and the tensile strength of a hot-rolled steel plate is larger than or equal to 780 MPa, the ductility is larger than or equal to 15%, the yield ratio is smaller than or equal to 0.75, the hole expanding performance is larger than or equal to 55%, and the use requirements for high strength, high plasticity and excellent hole expanding performance of automobile steel can be completely met.

The invention discloses high-strength high-toughness non-quenched and tempered front axle steel and a production method thereof. The high-strength high-toughness non-quenched and tempered front axle steel comprises the chemical components of, by mass, 0.21%-0.25% of C, 0.15%-0.35% of Si, 1.40%-1.60% of Mn, 0.20%-0.40% of Cr, 0.009%-0.020% of N, 0.020%-0.050% of Al, 0.040%-0.070% of S, less than orequal to 0.030% of P, less than or equal to 0.15% of Ni, 0.11%-0.16% of V, less than or equal to 0.06% of Mo, and the balance Fe and inevitable impurities, wherein Fn1 is equal to 0.79-0.85%, and Fn2is less than or equal to 1.80%. The steel has an excellent strength and low-temperature toughness, is low in production cost, and is suitable for being used on heavy-duty automobiles. Molten steel obtained through the method is good in liquidity, and a single tundish continuous drawing molten steel amount reaches 600 tons; a liquid level fluctuation of a crystallizer is within +/-3 mm, and the surface of a continuous casting billet is good; a yield strength of a front axle of an obtained product is 590-650 Mpa, a tensile strength is 850-916 Mpa, a percentage elongation after fracture is 19%-23%, a percentage reduction of area is 55%-58%, the normal-temperature impact toughness is 70-90 J/cm < 2 >, and the low-temperature (minus 50 DEG C) impact toughness is 27-45 J/cm < 2 >; and an average value of fatigue life tests of a front axle assembly reaches 1,300,000 times.

The invention discloses a machining process of a roller carrier shaft of a belt conveyer, and relates to the field of mechanical manufacturing of conveyers. The machining process comprises the following steps: (1) feeding a blank; (2) milling the end face and punching a center hole; (3) roughly and finely turning the excircle and chamfering; (4) milling a shaft and flattening a groove; (5) grinding the excircle; and (6) relieving stress to anneal. According to the machining process of the roller carrier shaft, the manufacturing precision and strength of the roller carrier shaft are improved through controlling the parameters of the machining procedures of the roller carrier shaft. Moreover, stress relief annealing is finally used in the procedures of the roller carrier shaft to relive the stress in the roller carrier shaft machining procedure. A procedure centralizing principle is used, so that the target can be realized and the cost can be reduced at the same time.

This invention involves a drip gas boronizing approach. The method contains the steps of: adopting ordinary drip gas carburizing furnace, heating the furnace to the temperature for boronizing, and dropping boriding agent containing trimethyl borate, methanol and chloridated rare earth and methanol to the furnace, decomposing and to form boride on the steel surface through adsorption and diffusion of boron atom decomposed by trimethyl borate. The invention has the advantage of uniform and compact leaking layer, good surface quality, Layer depth and surface boron content can be controlled; no need of cleaning workpiece after infiltration, with directly quenching after infiltration and low labor intensity; penetration enhancers without rank poison, non-explosive, with relatively good and safe, reliable working environment, without specialized equipments, commonly used carburizing furnace can meet the requirements, can handle all sorts of shapes and sizes workpiece, can be easy to achieve automatic control, with high efficiency, easy operation and high applicability.