Morphology and composition of plasma alloying of Cr–Mo layer

The surface morphology and the characteristics of the alloying layer were investigated by SEM after plasma Cr–Mo alloying and carburizing process. The results showed that a Cr-Ni alloying layer which was composed of α matrix and carbides distributed on it was formed in the surface of a Q235 steel using double glow plasma surfacing alloying technique. The shape of carbides was related to the concentrations of Mo, Cr and C in the alloying layer and exhibited strip-shaped or spherical carbides which became thick and big with increasing the carbon content. The maximum of carbide content in the alloying layer could reach about 45 wt.%.