摘要
研究发现２ＯＣｒ２Ｎｉ４钢在液体介质中应力比（含应力腐蚀Ｒ＝１）的增加可导致腐蚀疲劳门槛的降低和裂纹扩展速率的增加；当介质酸性增加时，门槛值有所降低但幅度不大，而平台区裂纹扩展速率则大幅度提高。研究表明，介质对裂纹扩展的促进作用取决于裂纹尖端区的应变和应变速率，并由此提出了活化因子和临界活化因子的概念及相应的计算公式。
The low-frequency fatigue behavior of 20Cr2Ni4 steel at various stress ratios(including SCCR=1)in aqueous environments is investigated. It is discovered that the fatigue threshold(△Kth) decreases and crack growth rate(da/dN)increases with increasing stress ratios.As the pH values increase,the △Kth decrease slightly but the da/dN at the plateauregion increases greatly. The effect of environments on crack growth relates to the strain and strain rate at crack tip.The concepts of activation factor(A) and critical activation factor(Ac)and the calculating equations are proposed.
出处
《北京工业大学学报》
CAS
CSCD
1994年第2期1-7,共7页
Journal of Beijing University of Technology
关键词
低碳钢
腐蚀疲劳
环境活化因子
mild steel,corrosion fatigue,environmental activation factor
