Abstract
In this study, AlSi10Mg alloy was fabricated using the laser-powder bed fusion (L-PBF) technology and then subjected to multi-pass friction stir processing (FSP) up to three passes. The microstructural evolution of the friction stir processed (FSPed) and as-built specimens were examined using scanning electron microscopy, electron backscatter diffraction analysis, and X-ray diffraction analysis. In terms of mechanical properties, microhardness distribution from the center of processed zone to the non-processed base metal was measured. FSP was found to drastically alter the distribution of Si particles within the ultrafine-grained structure of Al matrix in the processed region. The impacts of multi-pass versus single pass FSP on the degree of attained microstructural homogeneity in the alloy were also explored and comprehensively elucidated.