Abstract
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 is
removed from bulk feedstock to create a final geometry. Binder jet AM (BJAM) is a specific process in
the AM field in which a binder, or glue, is selectively deposited on a bed of spread powder feedstock and
cured. Binder is deposited with an inkjet printhead, which allows for high-resolution shaping of the
powder layers. Compared with other AM processes, BJAM is fast, efficient, and scalable. Further, BJAM
has 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 and
productivity of BJAM to enable multi-material printing, the next generation of AM technology. The aim
of this research is the design and manufacture of a purpose-built BJAM machine that can process multiple
materials in its normal operation. This binder jet additive multi-material manufacturing (BJAM3) machine
will be able to produce parts that have multiple materials intra- and inter-layer. An example of this would
be encapsulating metal spheres inside of a ceramic cube or vice versa. This BJAM3 process adds another
step of freedom to designing and manufacturing complex parts. The milestone for this work is to provide
details on the technical progress made to date on the development of multi-material binder jetting and to
facilitate simultaneous additive manufacturing of at least two different powder feedstocks.
