Binder Jet Additive Multi-Material Manufacturing for the Transformational Challenge Reactor

Additive manufacturing (AM) is a process in which material is deposited in a layer-by-layer fashion,thereby building up a geometry. This contrasts with subtractive manufacturing in which material isremoved from bulk feedstock to create a final geometry. Binder jet AM (BJAM) is a specific process inthe AM field in which a binder, or glue, is selectively deposited on a bed of spread powder feedstock andcured. Binder is deposited with an inkjet printhead, which allows for high-resolution shaping of thepowder layers. Compared with other AM processes, BJAM is fast, efficient, and scalable. Further, BJAMhas one of the largest material selections of the powder AM processes as it can process ceramics, plastics,metals, and virtually any powdered material. Thus, the opportunity exists to leverage the versatility andproductivity of BJAM to enable multi-material printing, the next generation of AM technology. The aimof this research is the design and manufacture of a purpose-built BJAM machine that can process multiplematerials in its normal operation. This binder jet additive multi-material manufacturing (BJAM3) machinewill be able to produce parts that have multiple materials intra- and inter-layer. An example of this wouldbe encapsulating metal spheres inside of a ceramic cube or vice versa. This BJAM3 process adds anotherstep of freedom to designing and manufacturing complex parts. The milestone for this work is to providedetails on the technical progress made to date on the development of multi-material binder jetting and tofacilitate simultaneous additive manufacturing of at least two different powder feedstocks.