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常用的淬火冷却方式主要有:①单介质淬火:工件只浸入一种冷却剂中,冷却到底。②延时淬火:工件在浸入冷却剂之前先在空气中降温以减少热应力。③双介质淬火:工件一般先浸入水中冷却,待冷到马氏体开始转变点附近,立即取出浸入油中缓冷,在水中的冷却时间一般按工件的有效厚度以3~5 mm/s的冷却速度进行计算。④分级淬火:工件先浸入低温熔盐中冷却,其停留时间一般等于总加热时间的1/3~1/2,最后取出在空气中冷却。⑤热浴淬火:工件只浸入150~180℃的硝盐或碱中冷却,停留时间等于总加热时间的,最后取出在空气中冷却等温淬火:工件浸入等温熔盐中进行冷却,熔盐温度和在熔盐中的停留时间由各
Quenching methods commonly used are: ① single medium quenching: the workpiece is immersed in a coolant, cooling in the end. ② delay quenching: the workpiece immersed in the coolant before cooling in the air to reduce thermal stress. ③ dual-media quenching: the workpiece is generally immersed in water cooling, to be cold until the martensite begins to change near the point immediately removed immersed in the oil slow cooling, the cooling time in water generally according to the effective thickness of the workpiece to 3 ~ 5 mm / s Cooling rate is calculated. ④ classification quenching: the workpiece immersed in low-temperature molten salt cooling, the residence time is generally equal to the total heating time 1/3 ~ 1/2, the last out in the air cooling. ⑤ hot bath quenching: the workpiece immersed only in the salt or alkali 150 ~ 180 ℃ cooling, residence time equal to the total heating time, and finally taken out in air cooling isothermal quenching: the workpiece immersed in isothermal molten salt cooling, molten salt temperature and The residence time in the molten salt consists of each