气流再压缩等离子弧焊接电弧行为  

Research on arc behavior in gas focusing plasma arc welding

作　　者：李天庆 陈璐[1] 张宇[1] 杨喜牟 雷玉成[1] LI Tianqing;CHEN Lu;ZHANG Yu;YANG Ximou;LEI Yucheng(Jiangsu University,Zhenjiang,212013,China)

机构地区：[1]江苏大学,镇江212013

出　　处：《焊接学报》2020年第5期50-55,I0004,共7页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(51605201);先进焊接与连接国家重点实验室开放课题研究基金(AWJ-16-M07);江苏大学高级人才基金资助项目(15JDG071);江苏省博士后科研资助计划(1601048C).

摘　　要：电弧等离子体行为对焊接接头组织结构和性能具有决定性作用,开展气流再压缩等离子弧特性研究对于指导先进材料的气流再压缩等离子弧焊接工艺和提高焊接接头质量具有重要意义.针对气流再压缩等离子弧焊接新工艺,基于流体动力学和电磁理论,建立气流再压缩等离子弧数值分析模型,采用ANYSYS Fluent软件,通过C语言进行二次开发,定量计算等离子弧温度分布、流场分布、电势分布,分析压缩气对等离子弧温度场、流场、电弧电压的影响规律.模拟结果表明,压缩气对喷嘴内的等离子弧温度分布基本没有影响,压缩气对喷嘴外的等离子弧具有拘束压缩作用;压缩气对等离子弧流场分布基本没有影响;压缩气能够提高电弧电压.相同电流条件下,与常规等离子弧焊接相比,气流再压缩等离子弧焊接电弧穿透能力有望提高.Plasma arc behavior plays a decisive role in the microstructure and properties of welded joint.Therefore,it is of great significance to study characteristic of gas focusing plasma for guiding gas focusing plasma arc welding advanced material and improving welded joint properties.The mathematical model of arc in gas focusing plasma arc welding as a new welding process,is developed based on fluid dynamics theory and electromagnetic theory.The model is conducted on software ANSYS Fluent with further development by C program language.The temperature distribution,velocity filed,potential of plasma arc are calculated quantitatively.And influence of focusing gas on arc temperature,plasma velocity and arc voltage is analyzed.Plasma temperature outside of nozzle is focused by focusing gas,while plasma temperature inside of nozzle is basically unchanged with or without focusing gas.Plasma velocity distribution both inside and outside of nozzle has no significant changes with focusing gas.Arc voltage in gas focusing plasma arc welding is larger than that in traditional plasma arc welding with the same welding current.Under the same condition on welding current,arc penetrability in gas focusing plasma arc welding will increase compared with traditional plasma arc welding.

关 键 词：等离子弧焊接 压缩气 电弧等离子体行为 温度场 

分 类 号：TG456.2[金属学及工艺—焊接]