Fabrication of in-situ TiC reinforced composite coating via plasma transferred arc process

In this work,the in-situ TiC particles reinforced composite coating was prepared by plasma transferred arc process on the surface of Q235 steel.Microstructures,phase composition and wear property of the coating were investigated.The results showed that the composite coating consisted mainly of γ-Ni,TiC,Cr₂₃C₆,Cr₇C₃,Ni₃Si,CrB,Cr₅B₃ and FeNi₃phases,and was characterized by fine TiC particles embedded in Ni matrix.The wear resistance of composite coating was significantly improved compared with that of the steel substrate.The wear volume loss of the substrate was 443 mm,which was about 9 times as that of in-situ TiC particles reinforced composite coating（49 mm）.It is mainly attributed to the presence of chromium carbide particles and in-situ TiC particles and their favorable combination with Ni matrix.