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本文研究了亚温(α+γ)区域淬火对高强钢30CrMnSiA 氢致延迟断裂的影响。结果表明,在900℃油淬和250℃回火之间增加一次自860℃(α+γ)区的亚温淬火能显著提高该钢的抗氢脆能力。可提高回火马氏体的氢致延迟断裂的下临界应力,降低裂纹扩展速率,而对回火索氏体组织影响不大。离子探针和 X-射线能谱分析发现亚温淬火在不同程度上消除了合金元素和杂质元素在奥氏体晶界上的偏聚;微量铁素体的存在,以及奥氏体晶粒细化都对改善钢的氢致延迟断裂抗力起着有益的作用。

The effect of quenching from intercritical temperature in(α+γ)region on hydrogen-induced cracking of a high strength steel 30CrMnSiA was studied. The results showed that an additional intereritical quenching from 860℃,per- formed between the oil quenching from 900℃ and tempering at 250℃,markedly improved the hydrogen embrittlement resistance of this steel.The minimum stress to hydrogen-induced cracking was increased by several times in steels with tempered martensltebut there was no effect on steel with sorbitic struc- ture having hardness below HRc36.The crack propagation rate of the steels with tempered martensite also decreased due to the intercritical quenching. The microanalyses of fractures with IMA and XPS showed that the segregation of impurities and the elements producing brittle failure at austenite grain boundaries was attenuated to a certain extent by this quenching.It would be bene- ficial for the superior hydrogen embrittlement resistance of the steel.In addition,the presence of minor ferrite and austenite grains refined could could also be helpful.