摘要
对２０Ｇ和２．２５Ｃｒ－１Ｍｏ钢经不同程度氢蚀后的常规力学性能与疲劳裂纹扩展行为进行了对比研究。并对氢蚀组织变化与裂纹扩展路径进行了显微观察。结果表明，氢蚀使２０Ｇ钢的疲劳裂纹扩展速率明显增大；扩展门槛值在氢蚀起始阶段显著降低，随后又呈增加趋势，对２．２５Ｃｒ－１Ｍｏ钢，由于元素Ｃｒ，Ｍｏ的作用，其氢蚀程度远低于２０Ｇ钢，从而未造成疲劳裂纹扩展速率的明显改变，分析表明，氢蚀后疲劳裂纹扩展门槛值的上升可以归因于曲折开裂路径造成裂纹闭合效应的增加。
The mechanical properties and fatigue crack growth behaviour for 20G and 2.25Cr-1Mo steels after hydrogen attack have been investigated. The microstructure after hydrogen attack and the propagation path of fatigue crack have been observed by optical microscopy. The results showed that hydrogen attack resulted in an obvious increase in fatigue crack growth rate for 20G steel;however, the threshold △K value decreased at the beginning of hydrogen attack, and increased at the successive stage for the same material.The 2.25Cr-1Mo steel showed a lower susceptibility to hydrogen attack due to the action of element Cr and Mo, not resulting in a significant change in fatigue crack behaviour.It is suggested that the increase in the threshold △K value could be attributed to the crack closure effect caused by the tortuous cracking path.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
1995年第1期B026-B030,共5页
Acta Metallurgica Sinica
关键词
氢蚀
疲劳裂纹扩展
裂纹闭合
合金钢
hydrogen attack, fatigue crack growth, crack closure steel 20G. Steel 2.25 G-l Mo
