摘要
文章选取了我国某类型高速列车常用的A7N01S-T5铝合金材料,进行了恒载荷应力腐蚀试验,对A7N01S-T5材料的应力腐蚀机理、应力腐蚀强度因子K1SCC和裂纹生长机制进行了研究.结果表明,A7N01S-T5铝合金的应力腐蚀破坏敏感性很高,其临界应力场强度因子K1 SCC为5.2 MPa.m1/2,仅为断裂韧度K1 C的0.15,对应的临界应力门槛值б为123MPa,仅为拉伸强度бb0.27.裂纹断口面有明显的舌状凸起和凹坑的存在.A7N01S-T5铝合金的应力腐蚀裂纹以沿晶开裂为主,形貌呈树枝状,同时相邻二次裂纹之间有竞争生长的关系.
Constant load stress corrosion test was employed to observe the stress corrosion mechanism, threshold value Klscc and crack growth mechanism of A7N01S-T5 aluminum alloy for high-speed train. The results showed that the sensitivity of stress,corrosion of A7N01 S-T5 was high. The value of the threshold K1 scc was on- ly 5.2 MPa · m1/2 and was only 0.15 times of the value of Klc. The value of the stress limit6was 123MPa and was only 0.27 times of the value of 6b- The tongue boss and cave holes were found on the fracture surface. The SCC crack morphology of A7N01 S-T5 aluminum alloy was dentric and along the crack of grain boundaries, the near secondary cracks were against with each other during growing period.
出处
《材料科学与工艺》
EI
CAS
CSCD
北大核心
2012年第4期134-139,共6页
Materials Science and Technology
基金
国家科技支撑计划资助项目(2009BAG12A07)
