Effect of ageing time on corrosion behavior of Mg-10Gd-4.8Y-0.6Zr extruded-alloy
(1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China;
3. Key Laboratory of Nonferrous Metal Materials Science and Engineering of Ministry of Education,
Central South University, Changsha 410083, China)
2. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China;
3. Key Laboratory of Nonferrous Metal Materials Science and Engineering of Ministry of Education,
Central South University, Changsha 410083, China)
Abstract: The corrosion behaviors of Mg-10Gd-4.8Y-0.6Zr extruded-alloys with various ageing time were investigated by immersion test and electrochemical measurements. The results show that the corrosion rate of the experimental alloy decreases with the increase of ageing time from 0 to 108 h. The corrosion resistance of the experimental alloy was found to increase with the increase of the size of the precipitate phases. The open circuit potential of the experimental alloy increases with the increase of the ageing time. The potentiodynamic polarization curves show that the cathodic over-potential increases with the increase of ageing time, leading to a decrease in the current density of anodic current plateau with the increase of ageing time.
Key words: Mg-10Gd-4.8Y-0.6Zr alloy; corrosion behavior; ageing time