Effect of rolling processing on microstructure and electrochemical properties of high active aluminum alloy anode
(School of Materials Science and Engineering, Central South University, Changsha 410083, China)
Abstract: The effect of rolling processing on the microstructure, electrochemical property and anti-corrosion property of Al-Mg-Sn-Bi-Ga-In alloy anode in alkaline solution (80 ℃, Na2SnO3+5 mol/L NaOH) was analyzed by the chronopotentiometry (E-T curves), hydrogen collection tests and modern microstructure analysis. The results show that when the rolling temperature is 370 ℃, the electrochemical activity of Al anode decreases gradually with the increase of pass deformation in rolling, while the anti-corrosion property is improved in the beginning and then declined rapidly. When the pass deformation of rolling is 40%, the Al anode has good electrochemical activity as good as the anti-corrosion property and with the increase of rolling temperature, both electrochemical activity and anti-corrosion property of Al anode increase first and then decrease. When the rolling temperature is 420 ℃, the aluminum alloy anode has the most negative electrode potential of about −1.521 V (vs Hg/HgO) and the lowest hydrogen evolution rate of 0.171 6 mL/(min·cm2). The optimum comprehensive performance of Al alloy anode is obtained.
Key words: Al alloy anode; microstructure; electrochemical property; anti-corrosion property