摘要
采用准1.2 mm的细焊丝,采用交流CMT方法焊接了厚1.5 mm的AZ31B镁合金板材,获得了平直均匀的焊缝。利用高速摄像机与焊接信号采集系统观察了焊接过程,交流CMT焊接为短路过渡,熔化等量焊丝的负半波能量只有正半波能量的36%。还观察了接头微观组织、并测试了接头硬度和抗拉强度,结果表明,交流CMT方法焊接的AZ31B镁合金接头,焊缝组织细小,热影响区组织有所长大,焊缝及热影响区的平均硬度分别为HV66和HV45;最大平均抗拉强度为235 MPa,约为母材的96.7%,其伸长率为8%,约为母材的76.2%。
1.5 mm thick AZ31 B magnesium plates were butt welded by VP CMT process with 准1.2 mm feed wire.The process of VP CMT welding was observed through image capture and welding signal sensor system. Droplet transfer mode was short circuit, while for commensurate feed wire energy input of electrode negative phase accounted for 36% of electrode positive phase. Microstructure and properties were studied. Grains in weld seam were refined obviously, while those in HAZ were coarsened, thus becoming weakness of the joint. Average micro hardness of weld seam was HV66, with HAZ HV45. The average ultimate tensile strength of welded joint was 235 MPa, 96.7% of base metal and elongation 8%, nearly 76.2% of base metal.
出处
《焊接技术》
北大核心
2014年第11期20-23,6,共4页
Welding Technology
