高强度马氏体钢中微合金元素对氢致延迟开裂的研究进展

Research Progress of Microalloy Elements on Hydrogen-Induced Delayed Cracking in High Strength Martensitic Steels

高强度马氏体钢的开发通过优化微合金成分设计,匹配合理热处理可以控制C、N等纳米化合物的析出,形成良性“氢陷阱”,进而降低材料在使用过程中的氢致延迟开裂风险。对比不同热处理工艺下Ti、Nb、Cu合金元素在马氏体钢中的析出形态及其氢捕获位点,并评价了析出相在高强度马氏体钢中氢捕获能力。结果发现氢捕捉能力大小排序为:NbC>TiC>晶界>ε-Cu>位错,并且微合金元素复合添加可以起到更好的抗氢脆作用。

The development of high strength martensitic steels can control the precipitation of C,N and other nano compounds by optimizing the composition design of micro alloy and matching reasonable heat treatment,and form a benign“hydrogen trap”,thus reducing the risk of delayed cracking caused by hydrogen in the process of application.This paper compared the precipitation forms and hydrogen trapping sites of Ti,Nb and Cu alloy elements in martensitic steels under different heat treatment processes,and evaluated the hydrogen trapping ability of precipitated phases in high strength martensitic steels.The results show that the hydrogen capture capacity is ranked as follows:NbC>TiC>grain boundary>ε-Cu>dislocation,and the compound addition of microalloying elements can play a better anti-hydrogen embrittlement effect.