Microstructure and wear behavior of Fe-based coating prepared by plasma transferred arc-welding

A new Fe-based alloy powder was designed to prepare coatings by plasma transferred arc-welding (PTAW) process on AISI304L stainless steel substrate. The microstructure and wear behavior of the relative coating were detected by XRD, SEM and a rubber wheel abrasive testing machine respectively, in comparison with that of the traditional NiCrBSi and NiCrBSi+25% WC coatings. The results show that the matrix of Fe-based coating consists of Fe-Cr solid solution and γ-Fe phase,surrounded by numerous dispersed Mo-rich borides and M₂₃(B,C)₆ hard phases,which contribute to support and strengthen the coating organization. The Fe-based coating exhibits high average hardness of 64.2 HRC,and excellent wear resistance which is better of that of the NiCrBSi+25% WC coating and exceeds 8 times of that of the NiCrBSi coating.