摘要
采用大功率光纤激光器对Mg-Mn合金进行一系列激光焊接工艺试验,并对焊缝成形的形成规律、接头的微观组织进行研究。使用金相显微镜分析测试手段,研究光纤激光焊接接头各区域的显微组织,分析主要焊接参数(焊接速度)对焊接质量的影响。试验结果表明:当焊接功率为2 200 W、焊接速度为1 500~1 800 mm/min时,焊缝成形良好,无气孔缺陷。Mg-Mn合金激光焊接在不同的焊接参数下,焊缝的晶粒中均存在等轴晶和柱状晶,且晶粒主要组织为α-Mg固溶体和Mg_8Ce金属间化合物。焊缝的组织形态受到焊接速度的影响比较明显,随着焊接速度的不断升高,焊缝的熔宽相应减小,且晶粒尺寸也随之减小。
Mg-Mn magnesium alloy with the thickness of 4 mm was laser beam welded by using the high power fiber laser to investigate the effect of welding velocity on the weld appearance quality and microstructure.The results showed that the sound joints without porosity were obtained in the range of the welding speed from 1 500~1 800 mm/min.The columnar grains were observed near the fusion zone.And the grains were changed into fine equiaxed dendrite near the weld center.The α-Mg matrix,massive Mn phases,Mg_8Ce inter-metallic compounds were observed in the joint.The greater difference of the microstructures of the joints was detected at the different welding speed.The weld width and the grain size of the joint were decreased with the increase of welding speed.
出处
《焊接》
北大核心
2017年第6期17-20,共4页
Welding & Joining
基金
陕西省教育厅科技基金项目(16JL1136)
兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室开放基金项目(SKLAB02014007)
关键词
晶粒尺寸
树枝晶
等轴晶
熔宽
气孔
grain size
dendrite
exquiaxed grain
weld with
porosity
