深冷处理对WE43A异质焊补接头组织及性能影响研究

Effect of deep cryogenic treatment on microstructure and properties of WE43A dissimilar repair welding joints

针对不同深冷处理对WE43A镁合金TIG焊异质补焊接头组织和性能的影响进行研究。结果表明,与焊态相比,随深冷时间的延长,深冷处理后WE43A镁合金异质接头的晶粒逐步细化且第二相从基体和晶界中析出。深冷处理后W43A镁合金TIG焊焊补接头的显微硬度变大,其耐蚀性有所提高,晶粒细化率最高可达54.4%,焊缝区显微硬度增大25.3%。综合来看,选用-100℃×8 h深冷处理工艺最优。

The effects of different cryogenic treatments on the microstructure and properties of dissimilar repair welding joint of WE43A magnesium alloy by TIG welding are studied.The results show that comparing with the as-welded,as the deep cryogenic time extends,after the deep cryogenic treatment,the grains of the dissimilar welded joints of WE43A magnesium alloy are gradually refined and the second phase precipitates from the matrix and the grain boundary,and the microhardness of WE43A magnesium alloy TIG welding repair joint increases,its corrosion resistance improves,the grain refinement rate can reach 54.4%,and the microhardness of weld metal zone increases by 25.3%.In general,the-100℃×8 h deep cryogenic process is the best.