Fabrication of porous CoCrFeMnNi high entropy alloy using binder jetting additive manufacturing

Abstract

Porous metallic components are known for their multifunctions in a variety of industries. However, the fabrication of porous metal parts via the conventional manufacturing processes, such as metal injection molding and metal sintering, is largely constrained due to their dependency on templates or supports. Additive manufacturing techniques have no such limitations. Binder jetting is a powder-bed-based additive manufacturing technique, and it has the inherent advantages in fabricating high porous components through the pores-by-process approach. In this work, the manufacturing process of porous CoCrFeMnNi high entropy alloy using binder jetting was investigated. Part porosities in the range of 35 %–40 % were achieved through binder jetting and subsequent sintering processes. X-ray computed tomography measurement indicated the morphology and size of the pores were uniformly distributed. The average compressive yield strength of the porous samples varied between 42–70 MPa, compressive elastic modulus varied between 3–12 GPa. Fracture surface investigations revealed transgranular quasi-cleavage fractures to be more dominant. The corrosion resistance of the porous CoCrFeMnNi was found to be comparable to the 316 L equivalent upon optimum sintering parameters. Overall, it is potential candidate for filtration applications.