Influence of copper plate positioning, zero tool offset, and bed conditions in friction stir welding of dissimilar Al-Cu alloys with different thicknesses

Abstract

Friction stir welding of dissimilar thickness aluminum and copper alloys was carried out without offsets by placing the copper at different positions, with horizontal and inclined bed conditions. The influence of the copper plate positions and bed conditions on macro-structure, microstructure, and mechanical properties were investigated. Optical microscopy, FE-SEM, EBSD, Tensile test, bending test, micro-hardness, and XRD analysis were carried out to understand the joint formation mechanism. The joint efficiency of 90% and 80.08% and bending angles of 93˚ and 35˚ were obtained, respectively, when the copper was placed at the middle position with horizontal and inclined bed conditions.