Cermet composite coating with a ductile Ni3Al binder phase and an in-situ Cr7C3 augmented phase

Abstract Boron doped Ni3Al intermetallic and in-situ Cr7C3 composite metal-ceramic powder were prepared by inert gas atomization method, and then the coating was prepared by HVOF. The Ni3Al alloys wet the in-situ ceramic particles well and form a continuous internal acicular crystalline phase. Mechanical property and wear performance testing showed the hardness, thermal shock performance and wear resistance of the coating are retained to temperatures of at least 700 °C. All mechanical properties in the range of 450–700 °C were found to be equal to or higher than comparable NiCr-based NiCr–Cr3C2 coating systems. Initial mechanism study shows that the small size and needle-like morphology of the ceramic particles are the important reasons for the good high temperature properties of the coating.