Properties and chemical composition of plasma arc welded Hardox450+FeW coatings

Abstract

In this study, Hardox450+FeW reinforced metal matrix composites (MMCs) were alloyed on AISI1020 substrate materials by the plasma arc welding (PAW) process. Microstructural characterizations of the coating layers were carried out by optic microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), X-ray diffractometer (XRD) and microhardness measurements. The results showed that there was a good bond between the substrate and the coating. The microstructural studies of the coating layer revealed the presence of a mixed dendritic phase structure of ferrite (alpha). The microhardness and the size of dendrites formed on the coated surfaces changed depending on the amount of FeW. The XRD results showed that Hardox450+FeW coatings were mainly composed of Fe3W3C, Fe2W, Cr3C2 and Fe7W6 phases. The Hardox450+25 wt.-%FeW composite coating represented the most appropriate combination in terms of microhardness.