Influence of hard inclusions on microstructural characteristics and textural components during dissimilar friction-stir welding of an PM Al–Al 2 O 3 –SiC hybrid nanocomposite with AA1050 alloy

Abstract

Owing to the advantages of nanocomposites for structural applications, we present microstructural evolutions and texture development during dissimilar friction stir welding (DFSW) of an Al-matrix hybrid nanocomposite (Al-2 vol.-% Al₂O₃-2 vol.-% SiC) with AA1050. It is shown that DFSW can successfully be performed at a rotating speed of 1200 rev min⁻¹ and a transverse speed of 50 mm min⁻¹ while locating the nanocomposite at retreating side. Formation of macro-, micro-, and nano-mechanical interlocks between dissimilar base materials (BMs) as a result of FSW tool stirring action possessed an impact influence on the mechanical performance of dissimilar welds. Electron microscopy revealed formation of a three-modal grain structure from microscale (>1 µm) to nanoscale (<100 nm) range in the stir zone of the joint materials. Texture components included a mixture of shear elements and ideal random orientations, as compared to the completely random and Cu-P preferred textures for the aluminum and composite BMs.