Potentials and challenges of multi-material processing by laser-based powder bed fusion

Multi-material additive manufacturing offers a multitude of opportunities for increasing functional integration beyond the current state of the art. However, the real potential is only vaguely described and there are also challenges alongside the new opportunities. This paper presents a systematic collection of the challenges to be overcome by laser-based powder bed fusion before it can provide industrially relevant multi-material processes. Amongst others, parameter adaptation to avoid micro-cracking, relevant process monitoring technologies (e.g., thermography-based layer monitoring) and potential approaches for powder separation (e.g., using ferromagnetism) are described. Furthermore, to exploit the full potential of multi-material designs, possible concepts for the integration of fully functioning mechatronic devices into multi-material parts are also presented.