J Mater Sci Technol ›› 1998, Vol. 14 ›› Issue (3): 259-264.

• Articles • Previous Articles     Next Articles

Aging Characteristics, Stress Corrosion Behaviour and Role of Mg Segregation at Grain Boundary in 7175High-strength Al Alloy

Renguo SONG; Ping GENG; Meiguang ZENG and Baojin ZHANG( Dept. of Materials Physics, Universityof Science and Technology Beijing, Beijing 1ooo83, China)(Dept. of Materials Science, Science College, Northeastern University Shenyang 110006, China)   

  • Received:1998-05-28 Revised:1998-05-28 Online:1998-05-28 Published:2009-10-10

Abstract: The aging characteristics, stress corrosion behaviour and chemical composition of grain boundary in 7175 high-strength Al alloy during long term aging process have been investigated by hardness measurement, constant elongation rate testing (CERT) and energy spectroscopy analysis. The results indicate that double peaks in aged state feature the hardness and strength of 7175 Al alloy Although the intensity of double peaks is almost equal, the stress corrosion resistance in the second peak-aged state is better than that of the first peak-aged state. The effects of Mg segregation on the binding energy of grain boundary have been calculated by using free electron theory developed by the authors. The results show that Mg segregation plays a significant role in controlling stress corrosion susceptibility which is consistent with the experimental results.