Effect of CeO2 on Microstructure and Bond Strength of Fe-Ni-Cr Alloy

Fe-Ni-Cr alloy powders with and without 0.4% CeO2 were flame sprayed on the surface of 1045 carbon steel substrate. The effect of rare earth oxide CeO2 on the interface layer and microstructure was investigated by X-ray diffraction analysis, SEM and EDS. Based on our previous work, comparison on the microstructure of a Fe-Ni-Cr alloy with and without 0.4% CeO2 addition was made. The correlation between the microstructure and bond strength was studied. The addition of CeO2 in Fe-Ni-Cr alloy shows promise results for providing good bonding strength as well as tribological properties.The results show that the hardness of the coatings can be improved by addition of 0.4% CeO2, and the shape of powders is more spheroidal. The combination of three aspects, namely small, well-distributed microstructure, the well-distributed matrix and promotion of diffusion leads to the improvement in bond strength of Fe-Ni-Cr alloy with addition of 0.4% CeO2.