| 摘要 |
PROBLEM TO BE SOLVED: To provide a heat treatment oil composition capable of reducing variation of cooling performance per parts during collective hardening and suppressing aging of the cooling performance when a heat treatment is conducted repeatedly while maintaining cooling performance at similar level to 2 kind 1 type oil of JIS K2242:2012 when the heat treatment is conducted on a metal material by hardening or the like.SOLUTION: There is provided a heat treatment oil composition containing (A) a base oil, (B) one or more kind selected from an oil resin and/or a derivative from the oil resin and having property second obtained from a cooling curve obtained according to a cooling performance test method of JIS K2242:2012 of 1.00 sec. or less and 300°C seconds which is a cooling time from 800°C to 300°C in the cooling curve of 6.00 sec. to 14.50 sec.SELECTED DRAWING: None |
