Structure and Properties of ZnAl-ER Composite Coating Prepared by Spraying
ZnAl/epoxy resin(ZnAl-ER)composite coating was prepared on the surface of bonded NdFeB mag-netic rings by air spraying.Scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),X-ray diffraction(XRD)and 3D laser confocal scanning microscopy(LCSM)were used to characterize the morpholo-gy,structure and chemical composition of the coating.The surface of ZnAl coating is layered structure with high porosity and large roughness.After compounded with ER coating,ER penetrates into the pores of ZnAl coating,which can effectively fill the pits and pores on the surface of ZnAl and reduce the surface roughness of compos-ite coating.ZnAl-ER coating has good corrosion protection effect,and its surface oxidation rate is significantly reduced.The corrosion resistance study shows that the neutral salt spray(NSS)time of ZnAl-ER/NdFeB is 240 h,and the corrosion current density is about one order of magnitude lower than that of NdFeB magnetic ring.More-over,the prepared coating has little effect on the magnetic properties of bonded NdFeB magnetic rings.