电阻点焊、塞焊及盲铆异种钢接头的拉剪强度对比分析

Comparative Analysis of Tensile-shear Strength of Resitance Spot Welding,Plug Welding and Blind Riveting Joints of Dissimilar Steel

以双相钢CR440Y780T与低合金钢CR340LA为基材,对比分析了电阻点焊、塞焊(MIG焊,焊丝分别为CuAl7与CuSi3)与盲铆三种连接接头的拉剪强度,为车身焊点修复方案确定提供了试验与理论依据。试验结果表明,CuAl7与母材的匹配程度优于CuSi3,焊接后结构强度较高,在薄板母材上开孔塞焊的结构强度也好于在厚板母材上开孔塞焊。盲铆的稳定性好,强度较塞焊更好,受人工操作影响小,但可操作性方面容易受到限制。对比三种连接方式的试验结果,电阻点焊接头强度最高,盲铆接头的强度约为电阻点焊的60%,塞焊接头(焊丝CuAl7)强度与盲铆接头相近,塞焊接头(焊丝CuSi3)强度最低。

Taking dual-phase steel CR440Y780T and low alloy steel CR340LA as the base metals,the tensile-shear strength of resistance spot welded joint,plug welded joint and blind riveting joint was compared and analyzed,which could provide experimental and theoretical basis for the determination of repair scheme of automobile body welding spot.The plug welding was finished by MIG welding,the welding wire is CuAl7 and CuSi3,respectively.The test results show that the matching degree between CuAl7 and base metal is better than that between CuSi3 and base metal,the structural strength after welding is higher.The structural strength of opening-hole on thin plate in plug welding process is also better than that on thick plate in plug welding process.The blind riveting process is more stable,the connecting strength is higher than that of plug welding,and manual operation has small influence on blind riveting,but its operability is easily limited.Comparing the test results of the three connecting methods,the strength of the spot welded joint is the highest,the strength of blind riveting joint is about 60%of that of spot welding joint,the strength of plug welding with CuAl7 wire is close to that of blind riveting joint,and the strength of plug welded joint with CuSi3 wire is the lowest.