差温轧制对7055铝合金厚板剥落腐蚀性能的影响  

Effect of differential temperature rolling on exfoliation corrosion properties of 7055 aluminum alloy plate

作　　者：聂辉文[1] 赖春明 聂俊红[1] NIE Hui-wen;LAI Chun-ming;NIE Jun-hong(Hunan Chemical Vocational Technology College,Zhuzhou 412011,China)

机构地区：[1]湖南化工职业技术学院

出　　处：《轻合金加工技术》2019年第12期16-23,共8页Light Alloy Fabrication Technology

基　　金：湖南省科教联合基金(2017JJ5022)

摘　　要：采用强制调控轧制过程表层与心部温差的方法,实现了7055铝合金60 mm厚板的差温轧制。对轧制后的板材进行双级固溶处理(390℃0.5 h+470℃1 h)和回归时效处理(185℃0.5 h+125℃22 h);采用剥落腐蚀、金相、SEM、EBSD、透射电镜等方法研究了差温轧制对板材不同厚度层组织与剥落腐蚀性能的影响,并与常规轧制厚板进行对比分析。研究结果表明:与常规轧制相比,差温轧制通过改善板材心、表温差,增大了厚板心部的变形能力,提高了变形均匀性,使厚板再结晶程度、晶粒平均尺寸和大角度晶界占比均有所增加,但其各层耐剥落腐蚀性能有所下降。The differential temperature rolling(DTR) was realized on the 60 mm thick 7055 aluminum alloy plate by controlling the temperature difference between the surface layer and the center in the rolling process. The rolled plate was treated with two-stage solid solution treatment(390℃0.5 h+470℃1 h) and regression aging treatment(185℃0.5 h+125℃22 h). The effects of differential temperature rolling on the microstructure and exfoliation corrosion of different-thickness layers were studied by means of exfoliation corrosion,metallography,SEM, EBSD and TEM.The plate produced by was compared with the plate by conventional temperature rolling(CTR). The results show that in the differential temperature rolling process, the temperature difference between plate core and surface is improved, the deformation ability and deformation uniformity of plate core are increased, and the recrystallization degree, average grain size and the proportion of grain boundary with large angle are increased, but the corrosion resistance of each layer is decreased to some extent.

关 键 词：7055铝合金 厚板 差温轧制 微观结构 剥落腐蚀 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TG339[金属学及工艺—金属材料]