摘要
研究了在循环载荷作用下V形和线形缺口X70管线钢试样在近中性溶液中的应力腐蚀裂纹的扩展行为。结果表明:线形缺口比V形缺口更容易使裂纹扩展,其原因是线形缺口试样的应力集中系数大于V形缺口试样的,且裂纹扩展速度随应力比的降低而增加;在裂纹扩展初期,环境是主要的影响因素,随着裂纹扩展的不断进行,力学作用逐渐增强,当应力强度因子幅ΔK达到某一值时,裂纹由稳定扩展转变为不稳定的快速扩展。
SCC propagation behavior of X70 pipeline steel specimens with V-shape and linear shape notches under cyclic loading in near-neutral solution was studied. The results show that linear shape notch made the cracks propagate easier than V-shape notch because the stress concentration factor of linear shape notch specimen was larger than that of V-shape notch specimen. And the crack propagation rate increased with the decrease of stress ratio. The environment was dominant affecting foctor of crack propagation at the beginning, and the mechanical role was enhanced gradually with the continuous propagation of reached a certain value, the propagation of cracks transferred cracks. When stress intensity factor amplitude △K from a stable stage to an unstable quick period.
出处
《机械工程材料》
CAS
CSCD
北大核心
2009年第4期39-42,共4页
Materials For Mechanical Engineering
基金
国家重点基础研究专项经费资助项目(G19990650)
青岛农业大学博士启动基金资助项目(630509)
关键词
X70管线钢
循环载荷
缺口
应力集中系数
裂纹扩展
X70 pipeline steel
cyclic loading
notch
stress concentration factor
crack propagation
