深冷处理温度对镁合金MIG焊接接头耐腐蚀性的影响  

Effect of Cryogenic Treatment Temperature on Corrosion Resistance of Magnesium Alloy MIG Welded Joint

作　　者：杨栋[1] YANG Dong(Teaching Center of Experiment and Practice,Shanxi Datong University,Datong 037003,China)

机构地区：[1]山西大同大学教学实验与实训中心,山西大同037003

出　　处：《材料保护》2020年第12期88-90,共3页Materials Protection

基　　金：山西大同大学校级青年科学研究项目(2018Q11)资助。

摘　　要：针对镁合金耐腐蚀性差的问题,采用不同深冷温度对AZ31镁合金MIG焊接接头进行了深冷处理,并测试与分析了不同深冷温度下焊接接头的腐蚀速率。试验结果表明:通过深冷处理细化焊接接头的微观组织,使组分更均匀,可以改善镁合金焊接接头的耐腐蚀性;同时,晶内析出弥散分布的第二相β-Mg_(17)Al_(12),将α相与外部环境相隔离,进而降低镁合金的腐蚀速率。其中,经过深冷处理(-190℃,6 h)后的焊接接头,其耐腐蚀性能最佳。Aiming at the poor corrosion rate of welded joints of magnesium alloy,the MIG welded joints of AZ31 magnesium alloy were treated by cryogenic treatment with different cryogenic temperature.The corrosion rates of the welded joints deep cryogenic treated with different temperature were tested and analyzed.Results showed that cryogenic treatment refined the microstructure and made the composition more uniform,therefore,improving the corrosion resistance of the welded joint of magnesium alloy.At the same time,the dispersed second phaseβ-Mg_(17)Al_(12)precipitated in grains isolated theαphase from the external environment,thus reducing the corrosion rate of magnesium alloy.The corrosion resistance of the welded joint was best after the deep cryogenic treatment at-190℃for 6 hour.

关 键 词：AZ31镁合金 耐腐蚀性 深冷处理 焊接接头 

分 类 号：TG156.91[金属学及工艺—热处理]