Abstract:
In recent ycars agreat attention is increasing ly paid to the application of rare earth elements in surface engineering along with the development of this field. This paper,aimingat to make best uses of Chinese rare earth elements resource and develop new application of rare earth elements in surface techniques,the effect of rare earth elements on microstructure and wear resistance of a iron base thermal spray-welding coating produced by a iron-base self-fluxing powder mixed with fractions of rare earth alloy powder was deeply investigated through friction and wear tests and elaborate SEM and TEM analyses,and its mechan ism was discussed based on the distribution and form of existence of rare earth elements in the coatings.The results showed that the addition of an appropriate amount of Si-Fe- Re additive can increase obviously the wear- resistance and load bearing capacity and the mechanisms can be explained by refininggrains,strengthening matrix by precipitation of LaB6 and purify grain boundaries by decrease segregation of element S.