回归再时效7A60铝合金在0.5mol/L NaCl溶液中的点蚀性能  

Pitting resistance of 7A60 aluminum alloy at retrogression and reaging in 0.5mol/L NaCl solution

作　　者：赵凯[1,2] 冯一可 宋诗哲[1] 寇益强[2] 唐子龙[1] 

机构地区：[1]天津大学材料科学与工程学院,天津300072 [2]核工业理化工程研究院,天津300180

出　　处：《海军工程大学学报》2012年第1期35-38,63,共5页Journal of Naval University of Engineering

基　　金：国家部委基金资助项目(H-bm)

摘　　要：采用腐蚀电化学的点蚀极化曲线并结合腐蚀形貌的扫描电镜分析的方法,研究了回归再时效(RRA)工艺处理7A60铝合金在0.5mol/L NaCl溶液中的点蚀行为,对其耐点蚀性能进行了评价,并探讨了RRA工艺改善该合金点蚀性能的机理。结果表明:采用120RRA工艺(120℃×24h预时效+195℃×0.5h回归+120℃×24h再时效)处理后,7A60铝合金在0.5mol/L NaCl溶液中的阳极极化曲线闭合环面积减小,再钝化电流密度Ipp降低,蚀孔较浅,RRA工艺在一定程度上改善了该铝合金在0.5mol/L NaCl溶液中的耐点蚀性能。According to electrochemical polarization curve testing and corrosion morphology analysis,the pitting resistance of 7A60 Al alloy under different aging conditions in 0.5 mol/L NaCl solution was mostly investigated.The results show that reasonable technology（120RRA） is pre-aged at 120 ℃ for 24 h,then retrogressed at 195 ℃ for 0.5 h and reaged at 120 ℃ for 24 h.Compared with peak aging（T6）,120RRA technology can improve the pitting resistance of alloy in 0.5 mol/L NaCl solution because of an decrease in the closed loop area of polarization curve,the re-passivation current density Ipp and the depth of pits of the alloy.

关 键 词：点蚀 7A60铝合金 回归再时效 再钝化 机理 

分 类 号：TG146.2[一般工业技术—材料科学与工程]