Research progress in multi-material laser-powder bed fusion additive manufacturing: A review of the state-of-the-art techniques for depositing multiple powders with spatial selectivity in a single layer

Additive manufacturing offers great potential and versatility for manufacturing high-quality and geometrically complex components. Multi-material laser-powder bed fusion is an emerging additive manufacturing approach where multiple materials are combined in order to manufacture multi-material components with new possibilities in product design and spatially tailored properties. Several multi-material delivery systems have been developed and a broad spectrum of applications have been demonstrated using multi-material laser-powder bed fusion. This work provides an overview in terms of architecture, construction and applications of all existing multi-material delivery systems developed for multi-material laser-powder bed fusion. Numerous challenges related to the deposition and processing of multi-materials which have been reported are discussed and potentials, which emerged through the use of multi-material laser-powder bed fusion are discussed together with the future perspectives.