双道次搅拌摩擦焊后Cu-Al接头的成型及界面组织

摘要

Single-pass and double-pass friction-stir welding tests on heterogenous metal plates of pure copper and pure aluminum with lap welding were conducted.Welding joint formation and microstructure were studied by means of scanning electron microscopy (SEM), energy spectrum analysis (EDS) and X-ray diffraction (XRD).The result showed that fine lap joints could be obtained with single-pass welding, but porous defect would easily form.The defect, however, could be removed by double-pass welding.The interface intermetallic compound of single-pass welding would be composed of Al2Cu and Al4Cu9 layers and Al2Cu layer alone would be found in double-pass welding interface.Total thickness of intermetallic compound layer after single-pass and double-pass welding would be less than 1μm, and the thickness of interface intermetallic layer after double-pass welding would be even.%对异种金属纯铜、纯铝板材进行了搅拌摩擦单道次焊与双道次焊试验,试验中采取搭接焊方式,使用扫描电镜(SEM)、能谱分析(EDS)、X射线衍射(XRD)对焊接接头成型及组织进行研究.结果 表明:单道焊能够形成良好的搭接接头,但易出现孔洞缺陷,双道次焊能消除单道次焊接产生的孔洞缺陷.单道次焊的界面金属间化合物由Al2Cu层和Al4Cu9层组成,双道次焊后的界面金属间化合物只有 Al2Cu层.单道次和双道次焊接后金属间化合物层总厚度小于1 μm,双道次焊后界面金属间化合物层更薄.