INVESTIGATION OF RELATION BETWEEN GRAIN BOUNDARY SEGREGATION AND BEHAVIOR OF STRESS CORROSION AND CORROSION FATIGUE IN 7050 ALUMINIUM ALLOY
Song Renguo;Zeng Meiguang;Zhang Baojin;Liu Jun;Jin Zhenhong(Northeastern University Shenyang 110006)
The relationship between grain boundary segregation and crack growth of stress corrosion and corrosion fatigue in 7050 aluminium alloy was investigated under various aging conditions in moist air environment. The effect of grain boundary segregation on fracture stress was also calculated using modified quasi-chemical approach. The results indicated that with increasing aging degree, the concentration of Mg segregated on grain boundary decreased and the ability of grain boundary to capture hydrogen was weakened, thus resulting in the decreasing percentage of grain boundary fracture stress reduction. It implied that the stress corrosion cracking susceptibility of the high strength aluminium alloy decreased and its corrosion fatigue resistance was improved.
【CateGory Index】： TG172.9