RELATIONSHIP BETWEEN QUENCHING MEDIUM-HARDNESS AND QUENCHING RATE

As long as the quenching cooling rate of steel is changed, different hardness values will be obtained. The main reason is that the structure of steel is different. When the cooling rate is slower and the C curve of the steel passes, the austenite transformation temperature is higher, the austenite will form pearlite, and the hardness of pearlite is smaller.

If the cooling rate is accelerated and the cooling curve does not cut through the C curve, the austenite will transform into martensite with higher hardness. The hardness of martensite is related to the carbon content in solid solution. Therefore, the hardness of martensite increases with the increase of% C content. However, when the content exceeds 0.77% C, the carbon solid solution content in martensite has not increased significantly, and the hardness change tends to ease. Cryogenic box, liquid nitrogen cryogenic box, ultra-cryogenic box, cryogenic equipment, cryogenic furnace, cryogenic treatment equipment, cryogenic assembly box, cryogenic assembly equipment, high and low temperature environment box