Evaluation of Liquid Doping Methods for Use in Laser Powder Bed Fusion

Laser powder bed fusion (LPBF) is an additive manufacturing (AM) process that is well known for its geometric versatility and high-quality parts. While the properties of LPBF parts are commonly superior to those made using other AM techniques, LPBF is generally limited to a single material in any given build. While LPBF can accommodate the integration of multiple components into a single part geometrically, the material limitation leads to over-designing to ensure that every component can complete their various functions. Some studies have shown potential methods of 3D composition control throughout a part, but these methods are subject to high cost increases due to build time increases and decreased powder recyclability. A new approach to multi-material LPBF uses liquid dopants to alter the composition in location-specific areas. The current study evaluates two different liquid deposition methods – direct write and inkjet deposition – in relation to their adaptability and utility in LPBF. Inkjet deposition is shown to have significant benefits compared to the direct write method.