Effect on the Hardening Behavior for Steel by Cooling Characteristics and Properties of Heat Treating Oil

摘要

In order to evaluate cooling performance of heat treating oil, it is general to use cooling curve or cooling rate curve by the silver specimen on JIS method or the Inconel specimen on ISO method. On JIS method, the indication of cooling performance is cooling curve's characteristics temperature and its cooling time from 800 to 400°C. It is possible to change the cooling performance that heat treating oil which is mainly consisting of mineral oil with various additives. However, even the heat treating oils which have almost the same cooling curve tend to change the hardening behavior of steel in actual quenching. It depends on heat treating oil's properties, main mineral oil's viscosity and etc. Especially it is necessary to select the heat treating oil which has appropriate cooling curves and properties.