Spring steel GCr4, GCr15, GCr18Mo ingredients imported manganese films, Pengcheng days shelf, related products are as follows:
         
        Domestic 50 55 65 75 85 65Mn 55si2mn 60Si2Mn 60Si2MnA
        60Si2CrA 65Si2CrVA 50CRVA 50CRMNT8A T10A
         
        U.S. imports of spring steel 10641065 1074 10845592606150
        304 304L TP304, 316L, TP316L, 301,301 B, 321 JIS420
        JIS420J2 440 440C
           
        Japan imported spring steel SUP3 SUP6 SUP7 SUP9 SUP10 SUP13 JIS420
        JIS420J2 SUS201 SUS303 SUS304 SUS316 SUS310
        SUS430 SUS410 SUS420 SUS440 SUS630 SUS631 K5 K7
   
        Plate, sheet, strip, wire, per rod, square bars, flat steel, hexagonal rods,
        Conventional shelf, especially custom specifications
        Spring strip steel products of high precision, good wear resistance, toughness, quality and stability. Welcome new and old customers call to discuss, telephone 0769 -81,889,927, Website: Http: / / ljh0205.cn.alibaba.com

Spring steels
Spring steel
        --- Spring spring steel main characteristics of work in the dynamic load, that is, in shock and vibration conditions, or under stress at work alternating the use of elastic deformation to absorb impact energy, a dampening effect.
        As the spring often withstand the vibration and enjoy long-term changes in the work under stress, mainly fatigue damage, it must be spring steel with high elastic limit and high fatigue limit. In addition, there should be adequate toughness and ductility, the impact force to prevent a sudden brittle fracture.
        In terms of technology, should have a good spring steel hardenability and low overheating, decarburization sensitivity. Reduce the surface roughness can increase spring fatigue life.
        In order to obtain the required performance, spring steel must have a high carbon content. Carbon spring steel of carbon content of 0.6-0.9%, and because carbon spring steel hardenability is poor, it is only used to produce cross-sectional dimension not exceeding 10-15mm springs. For the cross-section of a larger size spring, spring steel alloy must be used. Alloy spring steel carbon content in the 0.45-0.75%, and adding the alloying elements are manganese Mn, Si Si, Tungsten W, V V, Mo Mo, etc. Their main role is to improve the hardenability and temper resistance, enhanced grain refinement of ferrite and effectively improve the mechanical properties of spring steel, of which chromium Cr, tungsten W, Mo Mo can improve the high temperature strength of steel .
        In the hot springs forming state (diameter or thickness more than 10mm)
        State formed in the cold spring (10mm diameter or thickness in the following)
        Hot springs forming heat treatment process - forming in this way most of the hot springs forming and heat treatment carried out together, while the coil spring is mostly in the heat treatment after hot forming. This spring steel heat treatment is quenching + tempering temperature, heat treatment after the organization's physical care for the tempering. This organization of high elastic limit and yield limit, and a certain toughness.
        Spring cold forming heat treatment process - for cold-rolled steel sheet, strip or cold-drawn steel wire spring, due to cold plastic deformation of the material strengthening, spring has reached the required performance. Therefore, in the spring just after molding around 250C within 30min or so to heat stress treatment, to eliminate the cold forming internal stress generated by the spring, you can make spring stereotypes.
        Heat treatment of heat-resistant spring steel - internal combustion engine valve springs at higher temperatures, there are still some corrosive atmosphere, it is necessary to use a special spring steel and suitable heat treatment specifications.
        Common spring quenching defects and prevention measures
        (1) decarbonization (reduction in service life) - 1, using the salt bath furnace atmosphere furnace or heating system Zhu. 2, using the rapid heating process.
        (2) less than the hardness after quenching, a larger number of non-martensite, the center of the iron ferrite (generation and residual deformation, reducing the service life) - 1, choose a better hardenability of the material. 2, to improve the cooling capacity of quenching agent. 3, spring into the coolant temperature should be controlled in the Ar3 or more. 4, an appropriate increase in quenching temperature.
        (3) hot (fragility) - 1, strictly control the forming and quenching temperature. 2, enhanced quenching of metallographic examination.
        (4) cracking (brittle, severely reduce the life) - 1, control quenching temperature. 2, quenched to 250-300C when cold, remove the air-cooled. 3, tempering time
        Measures to improve the quality of the spring
        (1) thermomechanical treatment - the deformation of the steel heat treatment to strengthen and reinforce the two together to further enhance the strength and toughness of steel. Thermomechanical treatment of high, medium and low temperature of the points. High-temperature thermomechanical treatment is produced in the austenitic state quenching immediately after deformation can also be combined with forging or hot-rolled, quenched immediately after the hot forming. Thermomechanical treatment has been used in the production of automobile spring.
        (2) isothermal hardening spring - or let in for the smaller diameter of the spring can be enough to isothermal quenching, it can not only reduce the distortion, but also improve the strength and toughness, quenched after isothermal tempering the best once again, can increase the elastic limit, the tempering temperature and austempering temperature the same.
      (3) the relaxation process spring - spring for a long time to work in the external force, as the result of stress relaxation will produce small amounts of permanent (plastic) deformation, especially in high temperature spring, the phenomenon of stress relaxation at high temperatures is more serious, reduce the accuracy of the spring, this spring for the average precision is not allowed. Consequently, such spring in the quenching and tempering should be carried out after the relaxation treatment - for spring pre-load to deformation than the spring work possible deformation. 20C higher than the operating temperature and then under the conditions of heating, insulation 8-24h.
      (4) low-temperature carbonitriding - used tempering and low temperature carbonitriding (soft nitriding) a combination of technology, can significantly improve the fatigue life of spring and corrosion resistance, this process is used for spring rolls.
      (5) shot peening treatment - scratches, folding, oxidation and decarbonization and other surface defects tend to be the work of the spring when the local stress concentration and fatigue fracture source. If high-speed jet with small steel shot spring surface, not only to improve the surface quality of the spring to improve the surface strength, and to the surface in the compressive stress state, thereby enhancing the spring fatigue strength and service life.
        Handling Precautions
        (1) heat treatment before checking whether there is surface decarburization, cracks and other defects. These surface defects will seriously reduce spring fatigue limit.
        (2) quenching should pay special attention to prevent overheating and decarburization, good salt off