A Novel Two-Step, Transient Liquid Phase Sintering Process for Densification of Binder-Jet 3D Printed Superalloys

In binder-jetting of superalloys, challenges remain as the highly porous green bodies struggle to sinter to full density. Particle rearrangement during supersolidus sintering helped remove printing defects and promote densification, but the segregated elements are often detrimental. Here, a new two-step sintering process was applied to alloy 625. Results indicated that during the first step the material efficiently densified at supersolidus temperatures. Then, segregated elements diffused back into the bulk, resulting in a homogeneous microstructure.