Feasibility Study of Making Metallic Hybrid Materials Using Additive Manufacturing

A metallic hybrid structure, consisting of an Inconel-718 matrix and a Co-Cr internal structure, was successfully manufactured using laser direct energy deposition process. Characterizations were performed using energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), neutron-computed tomography (nCT), and electron back-scatter diffraction (EBSD) to verify the interfaces between Co-rich and Ni-rich phases. nCT revealed the internal structures to be continuous without cracking or significant intermixing due to inter-diffusion of Co and Ni (i.e., dissolved boundaries between the two structures). Minor porosity was detected. EBSD confirmed a good bond at the granular level. No precipitate phases were detected with XRD. EDS revealed dilution/intermixing between the Co and Ni interfaces presumably due to melt-pool overlay between the matrix and the internal structures.