Characterization of Interfacial Bonding Mechanism for Graphene-Modified Powder Metallurgy Nickle-Based Superalloy

A modified FGH96 superalloy using 0.1 wt% graphene was successfully prepared using the wet mixing method. The interfacial bonding mechanism between the graphene and the superalloy matrix was characterized using optical microscope, scanning electronic microscope, transmission electronic microscope and X-ray tomography. The results revealed that the graphene could be dispersed uniformly inside the matrix of the superalloy, and the bonding interface between graphene and the superalloy showed a rather diffusion instead of abrupt distinction, suggesting that the interface was formed via chemical fusion rather than a mechanical combination. The uniform dispersity of the graphene inside the superalloy matrix could improve the tensile properties significantly, including tensile strength, plasticity and yield strength. The existence of the graphene at the fracture surface further verified that the graphene could increase the effective bearing force of the material during the tensile test.