热处理温度对铝锌铟合金组织与电化学性能的影响

Effect of Heat-treatment Temperature on Microstructure and Electrochemical Performance of Al-Zn-In Alloy

采用金相显微镜、扫描电镜、恒电流法和动电位极化法考察了热处理温度对铝锌铟合金微观组织及电化学性能的影响。结果表明:470～530℃热处理可使合金组织均匀化,提高合金电化学性能。在470℃下固溶4h后炉冷处理的合金大晶粒内部出现微晶且晶粒内弥散析出细小点状第二相,晶界和第二相共同对合金起到良好的活化作用,使合金腐蚀形貌均匀、电流效率高达93.92%、电位负而且稳定。随温度升高至530℃,微晶晶界变粗、第二相开始长大,合金工作电位稍微正移,电流效率下降0.64%。

The effects of heat-treatment temperature on the microstructure and the electrochemical performance of Al-Zn-In alloys were investigated by OM, SEM, galvanostatic technology and potentiodynamic polarization method. The results show that after solution treated at 470-530℃ for 4 h and then cooled to ambient temperature in the furnace, microcrystallite and fine precipitated phases appear in the alloy which make the alloys dissolution homogeneous. So the alloys exhibit optimum comprehensive properties with high and steady negative operating potential, uniform dissolution and high efficiency. But with the heat treatment temperature increasing to 530℃, the precipitated phases start growing and current efficiency falls slightly.