连续点焊电极烧损对镁合金点焊质量的影响  

Effect of Electrode Burning in Continuous Spot Welding on Spot Weld Quality of Magnesium Alloy

作　　者：李乐乐[1] 吴志生[1] 赵菲[1] 帅朋 

机构地区：[1]太原科技大学材料科学与工程学院,山西太原030024

出　　处：《热加工工艺》2016年第5期63-66,共4页Hot Working Technology

基　　金：山西省科技攻关项目(20130322005-03);山西省基础研究项目(2015021130)

摘　　要：采用三相逆变点焊机对AZ31B镁合金薄板进行连续点焊。利用金相显微镜、扫描电子显微镜、万能试验机等检测技术研究了连续点焊过程中电极烧损对镁合金表面成形、熔核尺寸和抗剪力的影响。结果表明,随着焊点数的增加,焊点压痕变大,表面成形变差,熔核尺寸减小,熔核出现双核状,抗剪力总体减小。在熔核直径约4 mm、抗剪力在1200 N左右时抗剪断裂由纽扣式断裂向结合面断裂转变。AZ31B alloy sheet was welded continuously by three-phase inverter spot welder. The effects of electrode burning in continuous spot welding on surface forming, nugget size and shear force of magnesium alloy were studied by optical microscope（OM）,scanning electron microscopy（SEM） and universal tester. The results show that with the increase of weld points, the spot indentation becomes larger,and the surface forming becomes deteriorated. The nugget size reduces and the morphology of the nugget becomes dual-core shape. The shear force decreases integrally. The failure mode of shear fracture transfers from button type fracture into interfacial fracture, when the nugget diameter is about 4mm and shear force is about 1200 N.

关 键 词：电阻点焊 电极烧损 表面成形 熔核尺寸 抗剪力 

分 类 号：TG453.9[金属学及工艺—焊接]