Microstructure and growth characteristic of reinforced Ni-based composite coating by argon arc cladding

Ni-based composite coating reinforced by (Ti,Nb)C was prepared on the 16Mn steel substrate by means of argon arc cladding technique with the pre-alloyed powder of Ni60A, Nb, Ti and C alloy powders. The growth morphology of the (Ti,Nb)C particles and the microstructure as well as properties of coating were investigated by SEM, TEM, X-Ray, transmission electron microscope and microhardness tester. The results showed that the interface between the coating and substrate had excellent bonding and was free of pores and cracks. The microstructure of cladded coating consisted of (Ti, Nb)C particles, γ-Ni and eutectic structure M₂₃C₆. The in-situ synthesized (Ti,Nb)C presented octahedral shape. The connection growth was in the forms of octahedron verte-linked connection and edge-shared connection with form of petal-like shape and flocculation-like shape.