亚温淬火对30CrMnSi钢强韧性的影响

用30CrMnsi钢进行了亚温淬火试验。通过硬度试验、冲击试验测定了该钢经不同亚温淬火工艺规范后的硬度和韧性;用光学金相、电子金相分析了显微组织的变化,观察并比较了断口形貌。试验结果表明:30CrMnsi钢通过亚温淬火后,与常规热处理相比,在不降低强度的情况下,明显提高了韧性,抑制了可逆回火脆性,是一项值得重视的强韧化热处理工艺。这种强韧化效果,与亚温淬火前钢的原始组织、亚温淬火加热温度、加热速度等因素有关。在此基础上,对亚温淬火强韧化的机理进行了分析探讨。

EFFECT OF INTERCRITICAL HARDENING ON STRENGTH AND TOUGHNESS OF 30CRMNSI STEEL

This Paper deals with the intercritical hardening investigation of 30CrMn-si steel hardness and toughess, heat treated using different intercritical hardeni-ng regimes, have been determined with hardness testes and an impaet testes. Themicrostructures and features of bracture surface of the steel have been analysedby meatus of optical metallography and scanning electron microscapy. It has beenshown that the toughness of s0crMmsi steel trtate indtercritical hardening ishighes than that treated in conventional heat treatment regimes without thereduction in strength furthermore, the temper brittleness of this steel can becontrolled after intercritical hardening. It's obvious that this strengtheningand toughening technology is worth emphazing and studging further. However,the degree of increase in strength and toughness caused by this new technologyis related to the primary microstructure of this steel, the austenitizing tempera-ture of intercritical hardening and the speed of heating,the strengthening andtoughening mechanisms of intercritical hardening have been studied on the basisof the experiment.