摘要
为研究试样几何拘束对镍基合金应力腐蚀裂纹尖端力学特性的影响,对表征裂纹尖端扩展驱动力的应力应变及应力三轴度进行了分析。研究结果表明:试样中间层比表面层附近区域更先启裂,裂纹扩展速率也更大;由于裂尖拘束效应的影响,含裂纹的厚试样具有更大的裂纹扩展驱动力,更容易发生开裂和扩展;试样厚宽比B/W≥0.3时,裂尖拘束效应几乎不起作用。
To investigate the effect of compact tension specimen thickness on the mechanical characteristics at the tip of stress corrosion cracking in Ni-based alloys,the stress,strain and stress triaxiality that can characterize the crack driving force at the crack tips were analyzed.The results show that the specimen middle layer is more prone to crack initiation than the surface layer,and its crack propagation rate is higher.Due to the influence of crack tip constraint,the thicker specimen has greater crack driving force and is more easily for crack initiation or propagation.The crack tip constraint is hardly in effect when the thickness and width ratio B/W is no less than 0.3.
出处
《中国科技论文》
北大核心
2017年第22期2591-2594,共4页
China Sciencepaper
基金
国家自然科学基金资助项目(11502195)
西安科技大学博士启动金资助项目(2015QDJ041)
关键词
裂纹扩展速率
拘束效应
试样厚度
应力三轴度
扩展驱动力
crack growth rate
constraint effect
specimen thickness
stress triaxiality
crack driving force
