Grain boundary misorientation and texture development in friction stir welded SiCp/Al–Cu–Mg composite

Eight millimeter thick extruded 15 vol.% SiCp/Al–Cu–Mg composite was friction stir welded (FSW) and subjected to subsequent post-weld T4 temper. The grain boundary misorientation relationship in the nugget zone (NZ) was studied by using Kikuchiʹs-line technique of transmission electron microscopy. Texture development during FSW was examined by using X-ray diffractometry and subsequent orientation distribution function (ODF) analysis. It was revealed that the NZ was characterized by fine and equiaxed recrystallized grains with dominant high angle grain boundaries. Compared to that in the extruded composite, the texture in the NZ was significantly weakened. Post-weld T4 temper did not change the grain boundary characteristics and the texture orientation.