Surface modification of Hastelloy C-276 by SiC addition and electron beam melting

Electron beam surface melting of Hastelloy C-276 with the SiC addition is carried out to improve the surface properties. The resulted microstructure and non-equilibrium phases are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive system (EDS). The Hastelloy C-276 is successfully surface-hardened by electron beam melting, the surface hardening effect can be attributed to both microstructure refinement and eutectic phases produced by EB. During EB melting the SiC broke into small pieces and spread in the microstructure increasing the surface hardness by thirteen times.

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