【摘要】 采用剥落腐蚀实验、电化学阻抗测试、透射显微技术等方法,研究了不同冷轧变形量对Al-Zn-Mg-Cu合金组织和剥落腐蚀性能的影响。结果表明:随着冷轧变形量的增加,合金在EXCO溶液中剥落腐蚀增大。变形量主要通过改变晶粒形态及晶界析出相影响合金的剥落腐蚀性能。一方面冷变形导致合金晶粒纵横比增大,使得腐蚀裂纹尖端处产生的楔入应力增加,裂纹扩展速率提高;另一方面,较大冷变形合金时效时形成的连续晶界析出相易成为阳极腐蚀通道,也会加速剥落腐蚀进程。更多还原

【Abstract】 Effects of cold rolling deformation on exfoliation corrosion behavior and microstructure of Al-Zn-Mg-Cu aluminum alloy were investigated by the exfoliation corrosion tests,electrochemical spectroscopy(EIS) tests and transmission electron microscope(TEM).The results show that the exfoliation corrosion resistance decreases in EXCO solution with increasing the cold rolling reduction.The deformation is attributed to the changing grain morphologies and grain boundary precipitates in influence exfoliation corrosion performance.On one hand cold deformation causes grain aspect ratios increasing,makes wedge stress increase which is produced on the corrosion crack tip,and leads to the crack growth rate increasing;On the other hand,the grain boundaries precipitates which is formed by large cold deformation alloy aging easily become anode corrosion channel,and it can also accelerate exfoliation corrosion process.更多还原