Effect of Graphite Addition on Microstructure and Wear Resistance of Fe-Ti-V-C Cladding Layers

Fe-Ti-V-C Fe-based cladding layers were prepared on low carbon steel surface by laser cladding. The effects of addition amount of graphite in cladding powders on microstructure,hardness and wear resistance of cladding layers were investigated by means of X-ray diffraction,optical microscope,scanning electron microscope,energy dispersive spectrometer,micro-hardness tester and abrasive wear tester. The results show that the carbides (TiVC₂ and VC) were distributed evenly in cladding layers. The TiVC₂ was in form of either polygonal or a maple leaf shape while the VC was in form of a small block or a long and thin strip shape. The amount of carbides in cladding layers increased with the increasing addition amount of graphite. The presence of residual austenite in cladding layers was observed with high addition amount of graphite. The hardness and the wear resistance of cladding layers increased significantly and then decreased with the increasing amount of graphite. There was a tempering softening when multilayer cladding was employed. The higher the hardness,the more obvious the tempering softening.