Microstructure of cermet coating prepared by plasma spraying of Fe–Ti–C powder using sucrose as carbonaceous precursor

Abstract

In this paper, a kind of Fe–Ti–C composite powder for reactive plasma spraying (RPS) was prepared by heating a mixture of ferrotitanium and sucrose as a carbonaceous precursor, with an intention of carbonizing the sucrose. The tiny ferrotitanium particles were bound by the carbon obtained from the carbonization of sucrose. The carbon was a reactive element as well as a binder in the composite powder. While the composite powder was sprayed to deposit TiC/Fe composite coating by RPS, it was proved that the reaction between Ti and C was performed completely to form TiC, without impurity or residual raw materials in the coating. The composite coating is mainly composed of layers in which a mass of TiC particles are uniformly distributed and enwrapped within the crystal grains of metallic matrix, and the TiC particles in these layers are spherical or near-spherical in submicron-scale or nano-scale sizes.