固溶处理对7A55铝合金局部腐蚀性能的影响  

Influence of Solution Heat Treatment on Localized Corrosion of 7A55 Aluminum Alloy

作　　者：张新明[1,2] 吴泽政[1,2] 刘胜胆[1,2] 冯迪[1,2] 欧阳惠[1,2] 王婷[1,2] 

机构地区：[1]1南大学材料科学与工程学院,长沙410083 [2]有色金属材料科学与工程教育部重点实验室,长沙410083

出　　处：《材料工程》2014年第4期26-33,39,共9页Journal of Materials Engineering

基　　金：国家重点基础研究发展规划(“973”计划)项目资助(2012CB619500)

摘　　要：采用电化学测试、浸泡实验、金相显微镜、扫描电镜、透射电镜等实验手段研究固溶处理对7A55铝合金局部腐蚀性能的影响。结果表明:轧板中大量的第二相使轧板发生严重的腐蚀,整个表面被剥落下来。单级固溶的再结晶程度较低,亚晶组织细小,但合金残留第二相较多,耐蚀性能差。低温回复+高温固溶处理(450℃/1h+480℃/30min)可以将粗大第二相大部分溶解,且获得最少的再结晶分数和细小亚晶组织。实验结果表明,450℃/1h+480℃/30min固溶处理具有最佳的耐局部腐蚀性能。The influence of solution heat treatment on the localized corrosion of the 7A55 aluminum alloy were investigated by means of electrochemical test,immersion tests,optical microscopy,scanning electron microscopy（SEM）,transmission electron microscopy（TEM）.The results show that a large number of coarse constituent particles cause severe corrosion of the rolled plate and the entire surface is exfoliated.Single-stage solution treatment causes lower recrystallization fraction and small size of sub-grains,but the large number of remnant coarse particles results bad performance of corrosion resistance.The 450℃/1h＋ 480℃/30min solution heat treatment results in improved dissolution of coarse second phase particles,low recrystallization percentage and small size of sub-grains.The results indicate that the 7A55 aluminum alloy has the best localized corrosion resistance under the condition of the 450℃/1h＋480℃/30min solution heat treatment.

关 键 词：7A55铝合金 固溶处理 局部腐蚀 

分 类 号：TG166.3[金属学及工艺—热处理]