Chemical elements C Si Mn Cr PS content (%) 0.8 0.5 13.6 0.38 <0.03 <0.03 Soft annealed to HB 250 by refining the highest features (VD) + ESR refining (ESR), the organization is more pure and subtle, excellent corrosion resistance, polishing, good wear resistance, machinability, good dimensional stability when hardened. Uses high degree of polish and high demand within the module, high corrosion resistance of the plastic mold, manufacturing, medical, food industry products. S136 S136 is a good advantage of the corrosion resistance of plastic mold steel with excellent production characteristics, but more the following advantages: lower maintenance costs: die after long-term use, the cavity surface remains smooth original state. Mold in wet environments or storage operations, without special protection. Lower cost of production: die not because of the impact of cooling water corrosion, as there is a certain cooling cycles, increased die life. The benefits listed above, combined with high corrosion resistance S136 provides a low maintenance cost and high life of the mold, to achieve the best value for money. Meanwhile S136 through ESR (ESR) refinery, with a pure and subtle organization, so that the mold has good mechanical properties, high polished performance. Use S136 can be used with all the mold, due to its special nature, is more suitable for particular environments. Corrosion-resistant strain: the use of corrosive PVC acetate salts (ACETATES0) raw materials such as injection molding or die in a humid environment to work and save time, S136 resistant to water vapor, weak organic acids, nitrate, carbonate such as corrosion, mold made by the S136, if the operation in wet environments or corrosive under normal conditions of use of plastic materials, will not rust and contamination. If the tempering to 250 ℃ and polished to a mirror state, in particular, can show excellent corrosion resistance. Wear: use of large injection molding friction materials (including injection molding) or require a longer working time mold, such as electronic parts, discard-style meal knives, utensils and so on. High-quality finish of the surface: the production of optical products, such as cameras, sunglasses, chemical equipment, syringes, analytical instruments and plastic products. Physical nature of the material hardened, the hardness and tempered to 50HRC, at room temperature and high temperature data. Temperature ℃ 20 200 400 density Kf / m3 7850 7800 7700 elasticity N / mm 2 216 * 10 3 211 * 10 3 191 * 10 3 coefficient of thermal expansion from 20 ℃ from - 11 * 10_6 11.4 * 10_6 thermal conductivity W / m ℃ 16.5 21.5 23.5 Heat J / Kg ℃ 461 - - Tensile strength test material for the 25mm diameter rod, the second after 1025 ℃ quenching and tempering, the result of different hardness, such that: hardness of HRC 55 50 45 Tensile strength N / mm 2 2051 17,821,430 0.2% hardness N / mm 2 1610 1460 1280 Reduction of (%) 262 940 Elongation (%) 8 10 12 soldering normally welding tool steel should be avoided because of easy to crack. If you do the preparatory work before welding, welding parts such as warm-up, are more likely to be successful, welding and must take the following steps immediately: 1, eliminate stress - materials in soft annealed state welding must be done to eliminate stress. 2, tempering - quenching materials - tempered state welding, tempering must be done. Thermal annealing in the protection of the state, and then heated to 780 ℃ in the oven with the speed of 10 ℃ per hour, cooled to 650 ℃, and then in the air. After rough machining, stress relief, must be heated to 650 ℃, both hot 2 hours, slowly cooled to 500 ℃, and then in the air. Hardened :600-850 ℃ preheating temperature quenching temperature :980-1050 ℃ temperature (℃) hold time (min) before tempering hardness (HRC) 980 40 52 ± 2 1025 30 56 ± 2 1050 20 57 ± 2 are hot time to achieve the hardened steel center began to calculate the temperature, hardened must be protected against decarburization and oxidation of the oil quenching medium the salt bath furnace at 200-550 ℃ isothermal quenching, and then cooled in the air. Compressed air or circulating air abrasive grinding technology, the right, to avoid cracks, and can increase tool life. If the material in the ground state of low-temperature tempering, then the ground becomes very sensitive period, and only soft and open wheel type of grain can be used, and must have a good coolant. S136 in the hardened and tempered polished after the state, has a very good finish of 1, with particle size 180-320 of a preliminary grinding wheel or grindstone. 2, 400-800 sandpaper with grain or powder grinding. 3, 12.6 and using the particle size 3μm diamond paste, and polishing the fiber mat. Photo-etching S136 has a very evenly organization, very few impurities, it is suitable for photo-etching.