Heating temperature generally refers to the temperature of steel in quenching, which is divided into two kinds: ordinary and high magnetic quenching.
1．One kind of ordinary tempering
(1) Plain carbon steel: The heating temperature is generally below 840℃, and then decreasing with the increase of carbon content.
(2) Alloy steel: For iron-carbon alloy steel, when the carbon content is below 0.5%, the heating temperature is 450-550℃; when the carbon content is between 0.5-1.0%, the heating temperature is 510-580℃. For low-alloy steel containing nickel, chromium and molybdenum, the heating temperature is 700-830℃.
2．High magnetic quenching
(1) Plain carbon steel: The heating temperature of high-magnetic quenching is relatively high, generally 950-1250℃.
(2) Alloy steel: For low-alloy tool steel, the heating temperature is 1250-1320℃, and for high-alloy tool steel containing more alloy elements, the heating temperature is up to 1300-1350℃.
In quenching, the heating temperature must be controlled strictly. Too high temperature will make the material soften, and too low temperature will make the product fracture. In addition, it is necessary to carry out corresponding inspection to ensure that the quenching temperature of the material meets the standard requirements.
Generally speaking, the higher the carbon content, the higher the heating temperature of the steel should be. The heating temperature of steel should also be selected according to its alloy composition. If the alloy content is high, the heating temperature should be higher, otherwise it will cause incomplete tempering of the steel.
The quenching temperature of steel products also has a great influence on its mechanical properties, such as strength and hardness. Therefore, it is necessary to understand the characteristics and use environment of the steel product and then select the appropriate quenching temperature. In addition, the quenching speed is also very important. If the heating temperature is appropriate but the quenching speed is too slow, it will cause overheating of the steel and reduce its hardness. It is also necessary to strictly control the quenching process and make the steel products have the best properties.
