Microstructure and Wear Properties of Nanostructured Coatings Prepared by Wire Arc Spray

This paper investigated the effects of wear paramaters,such as sliding speed and load,on the wear properties of Fe-based nanostructured coating. A series of Fe-based nanostructured coatings were prepared by using wire arc spray. The microstructure of the coating was characterized by SEM,EDAX,XRD and TEM. The mechanical properties of the coating were measured by nanoindention. The wear tests of coatings were conducted on a MM200 wear tester. The microstructure of the coating consisted of amorphous phase and nanocrystalline (Fe,Cr) phase. The nano-grains with an average size of 46 nm were homogenously dispersed in an amorphous phase matrix. The coating was nearly full-densed with a porosity of 1.7% and high hardness. With the increase of sliding speed and load,the wear mass of the coating increased. The nanostructured coating had excellent wear resistance,i.e. the nanostructured coating was 2.6 times as high as that of the 3Cr13 coating. The failure mechanism of the coatings was brittle fracture.