Microstructure and Properties of TiB₂ Coating Deposited on Surface of 45 Steel by Electrospark

Ceramic coating TiB2 was deposited on the surface of 45 steel by electrospark.Micromorphology and element distribution of the coating were observed using optical microscope,scanning electronic microscope and EDS.Microhardness distribution and wear resistance of the coating were determined.The results indicate that the TiB deposited 45 steel demonstrated a typical four zone structure.The TiB2 coating was continuous,uniform,dense and lamination free.The grain size of the ferrite in HAZ was reduced greatly.Element Fe in the substrate diffused to the coating obviously,resulting in an atomic bonding between the coating and the substrate.The hardness of the coating was approximately 1 600 HV.The wear resistance of the TiB2-coated 45 steel exceeded that of quenched Cr12MoV steel.