Multi-Material additive manufacturing - Recycling of binary metal powder mixtures by screening

Multi-material additive manufacturing by laser powder bed fusion enables arbitrary material composition in components and thus opens new design possibilities. During the manufacturing process utilized powders are mixed and arising cross-contaminations are a hindrance for powder reuse. This paper investigates the possibility to process binary metal powder mixtures of different particle size distributions, which can be sorted and recycled by screening. Two different material combinations are processed over three multi-material manufacturing cycles and powder purities in the range of parts per thousand foreign particles can be achieved. Furthermore, material flow is calculated and general applicability of the recycling process is evaluated.