合金元素对铝阳极电化学性能的影响

通过正交试验法研究Mg,Sn和Hg元素对铝合金阳极电化学性能的影响,采用恒电流扫描法、动电位极化法和排水析氢法检测Al-Mg-Sn-Hg阳极的电化学性能和腐蚀性能,采用环境扫描电镜结合能谱分析研究A1-Mg-Sn-Hg阳极的表面形貌和显微组织.结果表明:Sn和Hg的加入使得一部分Mg与2种元素形成第二相,成为80℃、大电流密度下铝阳极活化的主要因素,并能很好地抑制析氢；另一部分Mg固溶在Al中,成为铝阳极保持活化状态的重要原因;得到了综合性能优良的Al-Mg-Sn-Hg铝合金阳极材料,它在电流密度为650 mA/cm2、80℃、4.5％的NaOH溶液中稳定电位为-1.707 V,析氢速率为0.38 mL/(cm2.min).

Effects of alloying elements on electrochemical performance of aluminum anodes

An Al-Mg-Sn-Hg alloy anode material was developed by orthogonally design to analyze the effects of additive elements on performance of Al alloy anode.Its electrochemical properties in alkaline medium were studied by galvanostatic test and potentiodynamic potential test.The corrosion resistance of Al alloy anode was studied by hydrogen evolution.The effects of additive elements on phase composition and microstructure of Al anode were studied by X-ray diffraction,scanning electron microscopy and energy dispersive spectroscopy.The results show that a part of Mg can form the second phase with Sn and Hg,which is the main cause of activating the aluminum at high temperature and large current density.Another part of Mg which solves in aluminum is an important factor to maintain aluminum activate.The stable potential of new developed Al-Mg-Sn-Hg anode is -1.707 V and the rate of hydrogen evolution is 0.38 mL/(cm2·min) at 80 ℃,650 mA/cm2 and 4.5% NaOH.