35CrMo钢的临界区热处理

Study on Intercritical Heat Treatment of 35CrMo Steel

研究了３５ＣｒＭｏ钢经不同温度临界区热处理后的显微组织与性能，并着重探讨了对其低温韧性的影响，试验结果得出：３５ＣｒＭｏ钢经临界区淬火并４７０℃中温回火后，与常规热处理态在保持等强度的同时，低温韧性有明显提高，－２０℃的冲击值提高８０％。文中对韧化机理作了讨论，认为是组织细化与细条状未溶铁素体共同作用的结果，此外还探索了用复合式加热淬火提高３５ＣｒＭｏ钢韧性的可能性。

In this paper,the microstructure and properties of 35CrMo steel after intercritical heat treatment of various temperatures have been studied and the effects of IHT on the cryogenic toughness were discussed.It is shown that the intercritical hardened and tempered steel can keep the strength level while its cryogenic toughness is increased to higher level than that of the coventional heat treated steel.and impact energy at -20℃ increase by 80 percent.The mechanism of toughness raising was discussed in the present paper,and it is considered that the microstruture refining and the presentation of ferrite contributed to the toughness of steel.