Additive manufacturing (AM) has unlocked new degrees of geometric design freedom that are not achievable through conventional manufacturing methods. Multi-material laser powder bed fusion (MM-LPBF) represents the next frontier in this evolution, enabling the integration of dissimilar alloys into a single component while leveraging the established benefits of AM such as design freedom, reduced material waste, and rapid prototyping-to-production capabilities. By depositing up to three distinct metal powders in one layer, MM-LPBF allows for the co-integration of materials with complementary properties, such as the high-temperature strength of superalloys and the exceptional thermal conductivity of copper, into a single, complex component. While the design potential of MM-LPBF is extraordinary, the process introduces significant technical challenges related to achieving robust metallurgical bonding between dissimilar materials. In contrast to single-material processing, MM-LPBF is considerably more challenging to establish ideal processing conditions to avoid undesirable metallurgical defects at the bi-material interfacial region. This talk will first present a framework for rethinking design and manufacturing principles in MM-LPBF: (a) strategies for computational part designs that incorporate multiple distinct material regions, and (b) engineered interfacial regions to mitigate residual stresses, metallurgical incompatibility, and melt pool instability. Finally, we will discuss emerging industrial applications where MM-LPBF offers distinct advantages ranging from high-strength, thermally efficient components for aerospace and defense to biocompatible, durable structures for biomedical devices. Together, these developments position MM-LPBF as a transformative approach for manufacturing multifunctional parts tailored to the increasingly complex design demands of 21st-century engineering.
