不同焊接工艺下等离子弧焊堆焊层组织演变研究  

Research on Structure Evolution of Plasma Arc Welding Layer Under Different Welding Process

作　　者：石端虎[1] 张文波[1] 沙静[1] 杨峰[1] SHI Duanhu;ZHANG Wenbo;SHA Jing;YANG Feng(School of Electromechanical Engineering,Xuzhou University of Technology,Xuzhou 221018 China)

机构地区：[1]徐州工程学院机电工程学院,江苏徐州221018

出　　处：《徐州工程学院学报（自然科学版）》2018年第2期47-51,共5页Journal of Xuzhou Institute of Technology(Natural Sciences Edition)

基　　金：江苏省自然科学基金项目(BK20141143);江苏省高校自然科学研究重大项目(16KJA430003)

摘　　要：采用等离子弧焊技术在16mm低碳钢板表面堆焊Fe90合金粉末,并用金相显微镜和扫描电镜对堆焊层微观组织进行观察,研究在不同焊接工艺下等离子弧焊堆焊层组织的演变规律.试验结果表明:堆焊层主要由马氏体、残余奥氏体和共晶碳化物组成,组织形态比较复杂;堆焊层存在明显的组织梯度,焊缝区的晶粒比较细小,近焊缝区主要为枝状晶,堆焊层中部为等轴晶;随着焊接电流增大,堆焊层组织晶粒尺寸变大,晶粒的分布也更加均匀;随着送粉速度增大,堆焊层晶粒尺寸变小,且组织更加均匀.Fe90 alloy powder was deposited on the surface of 16 mm mild steel by plasma arc welding.The microstructure of surfacing layer was observed by metallographic microscope and scanning electron microscopy.The evolution of plasma arc welding surfacing layer structure under different welding conditions was studied.The experiment results show that surfacing welding layer is mainly consisted of martenite,residual austenite and eutectic carbide,and the structure shape is very complex.Obvious structure gradient exists in surfacing welding layer,and the crystal grain of weld zone is very thin.The crystal grain nearby weld zone is dendritic crystal,and the crystal grain in the middle of surfacing welding layer is equiax crystal.With the increasing of welding current,the size of crystal grain becomes bigger,and their distribution is much evener.With the increasing of powder feed rate,the crystal grain becomes smaller,and the structure is much evener.

关 键 词：焊接工艺 等离子弧焊 堆焊层 组织演变 

分 类 号：TG455[金属学及工艺—焊接]