Influence of overlapping friction stir processing on microstructural evolution, texture development, and mechanical performance in Al6061

Abstract

In the current examination, a large-area stirred zone has been created in Al6061 through the application of overlapping friction stir processing. The investigation focused on examining the microstructural and texture changes in friction stir processed Al6061, using the electron backscattered diffraction technique. Electron backscattered diffraction images provided valuable insights into the recrystallization process, revealing the presence of fine-grained structure with high-angle boundaries in the large-area stirred zone attributed to intense plastic straining and dynamic recrystallization. The use of the tool caused significant plastic straining, resulting in the development of the A- (1 1 1) {1 1 0} texture component. Mechanical testing demonstrated a noteworthy increase in ductility after processing. However, the microhardness and strength were observed to be inferior to the base material due to elevated thermal cycling.