摘要
在空气和不同浓度H_(2)S环境中对X80管线钢进行了应力比为0.1和0.3的低频腐蚀疲劳试验,以获得疲劳裂纹扩展速率da/dN与应力强度因子幅值ΔK之间的Paris表达式,研究X80钢在不同条件下的疲劳裂纹扩展速率。结果表明:腐蚀环境能加速X80钢的裂纹扩展,当H_(2)S浓度为100 mg/L时,含H_(2)S环境中裂纹扩展速率是空气中的2.9倍;随着H_(2)S浓度的增大,裂纹扩展速率呈指数增大;随着应力比的增大,平均应力增大,裂纹闭合效应减小,裂纹尖端完全张开,材料与腐蚀介质接触面积增大,导致裂纹扩展速率增大。
X80 pipeline steel was subjected to low-frequency corrosion fatigue tests which were performed in air and in environments with different concentrations of H_(2)S at stress ratios of 0.1 and 0.3,to obtain Paris expression between fatigue crack growth rate da/dN and stress intensity factor amplitudeΔK and to investigate fatigue crack growth rate of X80 steel under different condition.The results showed that(a)the corrosion environment was likely to accelerates the crack growth in X80 steel,and when the concentration of H_(2)S was 100 mg/L,the crack growth rate in environment with H_(2)S was 2.9 times that in air;(b)as concentration of H_(2)S increased the crack growth rate increased exponentially;and(c)with the increase in stress ratio,the average stress increased,the crack closure effect decreased,the crack tip opened completely,the contact area between the material and the corrosive medium increased,thus resulting in the increase in crack growth rate.
作者
田万鹏
TIAN Wanpeng(Hunan Automotive Engineering Vocational College,Zhuzhou 412000,Hunan China)
出处
《热处理》
CAS
2023年第6期14-19,共6页
Heat Treatment
基金
2021年度湖南省教育厅科学研究青年项目(21B0886)。
关键词
应力比
腐蚀环境
疲劳裂纹扩展速率
裂纹闭合效应
stress ratio
corrosive environment
fatigue crack growth rate
crack closure effect
