31results about How to "Eliminate surface stress" patented technology

This invention provides a method for eliminating the surface stress of a silicon wafer comprising forming one or more anti-stress groove(s) on the surface of the silicon wafer. These anti-stress grooves can reduce or eliminate the surface stress of silicon wafer effectively to avoid the formation of slip lines and dislocation arrangements, which may induce the p-n junction to conduct or the leakage current to increase. The process is highly efficient and low in cost. It is simple to manage and does not require additional equipment beyond that already used for processing of silicon wafers.

The invention discloses a heat treatment process for an iron core of a motor and belongs to the technical field of the manufacture of motors. The process comprises the following steps of: (1) raising the temperature of an annealing furnace, and introducing DX gas into the annealing furnace after the temperature of an annealing zone of the annealing furnace is raised to 690 to 730 DEG C; (2) placing a motor iron core to be treated on a conveying belt of the annealing furnace for heating treatment; (3) introducing saturated steam into a bluing zone of the annealing furnace to ensure that the iron core which is subjected to heating treatment and enters the bluing zone is blued; and (4) cooling the iron core which is blued, and taking out. By the heat treatment process, the surface stress of iron core sheets is eliminated, the isotropy and residual magnetism are eliminated, the input power of the iron core is reduced, a damaged oxide film is repaired through bluing treatment, and the insulation between the sheets is increased; and C in an unstable valence state in a sheet material is displaced through reducing gas, so that the structural compactness of the material is improved, the stability of the material is increased, and the efficiency of the iron core is improved.

The invention provides a method for reducing the stress of tempered glass and a method for recycling defective glass products, and relates to the field of touch screen production. The method for reducing the stress of tempered glass includes the following steps: A) preheating: placing the lithium silicate tempered glass in a Preheating at 290-350°C for 2-5h; B) ion exchange: placing the preheated tempered glass in a mixed molten salt of sodium nitrate and lithium nitrate, and ion-exchanging at 382-450°C for 10-120min, wherein, In the mixed molten salt, the weight percent of the sodium nitrate is 71-79%, and the weight percent of the lithium nitrate is 21-29%. Using the method for reducing the stress of the strengthened glass can alleviate the lack of a technical problem in the prior art that is suitable for eliminating the stress of the lithium silicate strengthened glass, and achieve the purpose of reducing or eliminating the stress of the lithium silicate strengthened glass.

The invention relates to a controlled cooling and controlled rolling method for bearing steel wire carbide network control. ℃~880℃; control the spinning temperature from 750℃ to 850℃; use EDC water bath isothermal quenching and cooling to control the continuous coil cooling online, control the cooling speed 2.0℃ / s~10℃ / s, and control the final cooling temperature 620-630 ℃; after isothermal quenching in EDC water bath, add hood and slow cooling, and control the temperature of hood to be 400 ℃ ~ 500 ℃; after slow cooling, collect coils, and air-cool to room temperature. Using EDC water bath isothermal quenching cooling + hood slow cooling to control the cooling of the coil after controlled rolling, which can effectively inhibit the precipitation of carbides during the cooling process, obtain a non-equilibrium microstructure, and form a small strip or hemispherical shape Carbides, the final carbide network is controlled.

The invention belongs to the technical field of car parts and relates to a preparation method of a car door handle. The preparation method comprises the following steps that (1) a PC and ABS compositeis injected into a mould cavity so that a car door handle blank is obtained; (2) the car door handle blank is arranged in a bisphenol A type epoxy resin solution and then taken out to be put in a plasma reaction device and vacuumized, gas is supplied into the plasma reaction device, and surface modification treatment is carried out so that a surface modified blank is obtained; and (3) the surfacemodified blank is subjected to primary electronickelling, baking, then secondary electronickelling and drying, so that the car door handle is obtained.

The invention discloses a direct forming manufacturing method of a metal-based multilayer / gradient composite board and a process unit of the direct forming manufacturing method. Scale, corrosion materials and other impurities on the joint surface of a base board are removed through chemical cleaning, the cleaned surface is subjected to gradient power electromagnetic induction heating or laser bombardment surface treatment, all phases near the joint surface are fully dissolved, a solid solution is enhanced, toughness and corrosion resistance are improved, the surface stress of the board is eliminated, and surface laser treatment is conducted to improve the binding property of a composite layer; raw materials of the composite layer are added and injected through powder laying, a high-energy heat source is adopted for irradiation or induction heating to melt powder, metallurgical bonding is formed between the composite layer and a base, and control over the final shape of a cold / hot-rolled board is conducted. The obtained multilayer / gradient composite board is compact in surface structure, bonding between the composite layer and the base and between layers is good, and the interlayer bonding performance of the composite board is remarkably improved. The process is high in flexibility, and the production period of the metal-based composite board can be greatly shortened after the process is combined with an existing continuous casting technology.