Revealing the Hierarchical Microstructure of Innovative Additively Manufactured Metal Parts with Conventional Light Microscopy

Abstract

Additively manufactured parts are characterized by a peculiar microstructure, originated by the distinctive layer-by-layer process. In case of additive technology based on the localized melting of a metallic feedstock, as laser-based powder bed fusion (LPBF), the resulting microstructure has a hierarchical arrangement, consisting of macro- and microscopical features affecting the final properties. Commonly, several advanced metallographic techniques are adopted in order to reveal the LPBF microstructure. However, main microstructural features can be also qualitatively appreciated by means of conventional light microscopy. The present work aims at describing how the peculiar LPBF microstructure of the Co28Cr6Mo alloy can be characterized, along with its main microstructural features, by means of the sole light microscopy.