Characterization of Recycled Metal Powder for Assessing Its Reusability in Additive Manufacturing of Engineering Parts and Components

Abstract

Additive manufacturing technologies such as Laser Powder Bed Fusion provide unprecedented abilities to manufacture complex 3-D parts and structures; however, the process produces unused metal powder that can undergo significant change in particle size, chemistry and morphology. The ability to recycle the used powder that is typically found within the build volume and in the overflow compartments requires a thorough chemical and structural analysis in order to determine the extent of reusability. In this context, characterization of virgin powder and used powder for a nickel-based alloy was performed in this work in a rigorous fashion to compare and contrast properties such as particle size distribution, morphology, and composition. Characterization of particle size distribution was performed using a traditional microscopy method and that information was later compared to measurements of surface profile using Coherent Scanning Interferometry. Reusability was assessed using these results and suggestions on how to introduce methods of in-situ powder analysis are discussed.