Stress Corrosion of an Aluminum Alloy in Sodium Chloride Solution under Different Temperatures and Stresses

This paper applies subjective speckle method to investigate the effects of temperature and stress on the initial process of stress corrosion of an aluminum alloy 2024-T3. Considering the sensitivity of this observational method, the roughness of surface is used to represent the degree of corrosion. Stress corrosion experiments are carried out by displacement-controlled loading on specimens of Al2024-T3 in the thickness of 2 mm board in 3.5% sodium chloride solution. The solution is controlled at several temperature levels from 22°C to 80°C. The results of experiments show that: the rate of corrosion increases fast concomitance the increase of temperature when stress is constant; at the same temperature and the load range used, the effect of stress is not very evident on the rate of corrosion; the effect of temperature is higher on the rate of corrosion in the stress corrosion than that in general corrosion without stress.