Formability analysis of dissimilar friction stir welded AA 6061 and AA 5083 blanks by SPIF process

In this paper, formability of dissimilar friction stir welded AA 6061 and AA 5083 blanks during single point incremental forming (SPIF) is investigated numerically and experimentally. Sheets from AA6061, AA5083 and FSWed AA6061 to AA5083 are formed by SPIF with different cone angles, and the limiting wall angles are determined. Additionally, the effects of SPIF and FSW processes on the microstructure, mechanical properties and fracture mode are investigated. The empirical results demonstrate that the formability of dissimilar FSWed sheets are not so much different from that of the base metal sheets. Dissimilar FSWed specimen is fractured from the AA 6061 base metal and far from the FSWed region. Although investigation of the fracture surfaces of the tensile tests shows a ductile fracture for AA 5083, AA 6061 and dissimilar FSWed sheets, it is a combination of ductile and brittle fracture after the SPIF. Furthermore, the SPIF of FSWed sheets is simulated numerically using the ABAQUS/Explicit. The results show that the thickness and the major strain have uniform distributions for both FSWed and base metal sheets. On the other hand, minor strain has a non-uniform distribution in the wall of the formed conical part of the FSWed sheet, despite the base metal sheets.