Formation and properties of Fe-based amorphous/nanocrystalline alloy coating prepared by wire arc spraying process

Wire arc spraying process was used to deposit FeBSiCrNbMnY amorphous/nanocrystalline alloy coating onto stainless steel substrate. The microstructure of the coating was characterized by using X-ray diffraction (XRD), scanning election microscopy (SEM) equipped with energy dispersive X-ray analysis (EDXA) and transmission electron microscopy (TEM). The coating is about 500 mu m in thickness with fully dense and low porosity. The microstructure of the coating is classified into two regions, namely, a full amorphous phase region and homogeneous dispersion of alpha Fe, Cr nanoscale particles with a scale of 30-60 nm in a residual amorphous matrix region. The formation mechanism of the amorphous and nanocrystalline alloy was discussed. Mechanical properties, such as microhardness and wear resistance of the coating were also analyzed. The Vickers hardness of the coating is around Hv = 900-1050. The relatively wear resistance of the amorphous/nanocrystalline alloy coating is about 3 x than that of crystalline structure 3Cr13 martensite stainless steel coating under the same wear testing condition. The FeBSiCrNbMnY amorphous/nanocrystalline alloy coating has high microhardness and excellent wear resistance. (C) 2009 Elsevier B.V. All rights reserved.