中间层对SiC_p/6063Al复合材料电阻点焊接头性能的影响

Effect of intermediate layer on properties of SiC_p/6063Al composite resistance spot welded joints

采用Sn3.0Ag0.5Cu中间层对低体积比SiC_p/6063Al复合材料进行电阻点焊,通过剪切试验以及SEM、EDS和XRD分析Sn3.0Ag0.5Cu中间层和点焊工艺对点焊接头组织及性能的影响。结果表明:Sn3.0Ag0.5Cu作为中间层可有效与母材形成混合熔核,显著改善母材直接点焊后熔核中SiC颗粒偏聚现象,在点焊电压和时间分别为124 V、2.2 s时,接头剪切强度达到100.17 MPa,断裂主要发生在熔核及熔核边缘母材处,断裂形式是以韧性断裂为主的混合断裂。因此,Sn3.0Ag0.5Cu中间层可有效提高低体积比SiC_p/6063Al复合材料电阻点焊接头的结合强度。

Sn3.0Ag0.5Cu intermediate was used to perform resistance spot welding on 15% SiC_p/6063Al composites,and the effect of Sn3.0Ag0.5Cu middle layer and spot welding process on the microstructure and properties of spot welding joints was analyzed by shear test,SEM,EDS and XRD. The results show that Sn3.0Ag0.5Cu can effectively form a mixed nugget with the base metal as the intermediate layer,which significantly improves the segregation of SiC particles in the nugget after direct spot welding of the base metal. The shear strength reaches 100.17 MPa when the spot welding voltage and spot welding time are respectively 124 V and 2.2 s. The fracture occurs mainly at the base of the nugget and the edge of the nugget,and the fracture pattern is a mixed fracture dominated by ductile fracture. Therefore,Sn3.0Ag0.5Cu intermediate can effectively raise the combination strength of the resistance spot weld of low volume percent SiC_p/6063Al composites.