Correlative spatter and vapour depression dynamics during laser powder bed fusion of an Al-Fe-Zr alloy

Abstract

Highlights Investigate the correlation between spatter dynamics and keyhole/depression morphology during laser powder bed fusion. Discover rear rim droplet spatter that occurs at the keyhole rear rim due to the interaction between high-temperature gas/vapour and liquid metal. Uncover spatter-induced surface cavity mechanism as small spatter particles are accelerated towards the powder bed after laser-spatter interaction. Recommend low energy density (and high scan speed) printing strategies for minimising spatter and surface defects.