Effect of rare earth on oxidation resistance of iron base fluxing alloy spray-welding coating

Recently, the studies on application of rare earth (RE) in spray-welding materials has attracted more and more attention. Iron base fluxing alloy powder has been widely used as spray-welding materials due to some of its advantages, such as lower price and good wear resistance. However, its oxidation resistance at high temperature is poor, therefore, RE has been used to improve its properties in the present study. The iron base fluxing alloy powder containing mixed RE alloy were prepared by using the smelting–atomizing process, the coating samples were prepared by using the oxide-acetylene flame spraying process. And the effect of RE on oxidation resistance of iron base fluxing alloy spray-welding coating has been studied. Moreover, the oxide layer of the coating samples was analyzed by using scanning electron microscope (SEM) and the X-ray of electron dispersion analysis (EDAX). It has been shown that the addition amount of mixed RE alloy of 0.2 wt% is suitable. Based on the experimental results the mechanism of RE function has been discussed.