镁合金交流TIG和脉冲TIG组织性能分析  

Microstructure and property analysis of magnesium alloy welded with AC TIG welding and pulsed TIG welding

作　　者：王生希[1] 宋刚[1] 刘黎明[1] 

机构地区：[1]大连理工大学三束材料表面改性国家重点实验室,辽宁大连116024

出　　处：《焊接学报》2006年第9期63-66,共4页Transactions of The China Welding Institution

基　　金：教育部新世纪优秀人才支持计划(NCET-04-0271);教育部优秀青年教师资助计划项目

摘　　要：采用交流TIG和交流脉冲TIG两种焊接方法焊接变形镁合金AZ31B板材,利用高速摄像机和红外热像仪研究稳定焊接过程中的电弧形态和焊接温度场,观察焊接接头的微观组织并进行力学性能拉伸试验。发现脉冲焊接在峰值电流加热时的电弧形态明显大于交流TIG焊接时的电弧。对比焊接温度分布曲线可以看到,脉冲焊接时熔池两侧区域的冷却速度更快。脉冲焊接接头的热影响区更窄,而且晶粒更细小均匀。拉伸结果显示交流脉冲TIG焊接接头强度高于交流TIG焊接接头强度。AC TIG(AC:alterative current;TIG:tungsten inert-gas) welding and pulsed TIG welding were adopted to join the distorting magnesium alloy AZ31B plates.The electric arc was studied with high speed camera and the infrared thermal imaging system.The microstructures of joints were investigated and tension test was conducted.It was found that the electric arc of pulsed TIG welding was bigger than that of AC TIG welding when in the peak current.The temperature curve showed that pulsed TIG welding had a high cooling rate.The crystal grains in the heat affected zone were finer and the heat affected zone was smaller when welded with pulsed TIG welding.Tension test showed that the joint had high strength.

关 键 词：镁合金 交流钨极惰性气体保护电弧焊接 脉冲钨极惰性气体保护电弧焊接 微观组织 抗拉强度 

分 类 号：TG403[金属学及工艺—焊接]