点击次数：

论文类型：期刊论文

发表时间：2019-06-01

发表刊物：MATERIALS

收录刊物：SCIE、PubMed、EI

卷号：12

期号：11

ISSN号：1996-1944

关键字：friction stir welding with cover sheet; weld reinforcement; mechanical properties; microstructure

摘要：Friction stir welding can realize high-strength aluminum alloy joints. In this study, friction stir welding with cover sheet (CFSW) is proposed to solve the thinning caused by the tool shoulder and reduce the heat-affected zone. The microstructures and mechanical properties of CFWS were also studied. After the cover sheet was added, a reinforcement was formed on the weld surface, which compensated the thinning caused by the friction of the tool shoulder. As the cover absorbed heat from the shoulder, the width of the heat-affected zone of the welded sheet became smaller than the diameter of the shoulder. Without milling the cover sheet, the tensile strength of the 5754 aluminum alloy joint reached 94% of that of the base metal. The fracture position was the heat-affected zone of the forward-side weld joint. After the cover sheet was added, the stress concentration shifted from the thinning area of traditional friction stir welding to the outside of the welding seam.