Microstructure and properties of in-situ TiC-TiB₂/Ti composite coating by argon arc cladding

TiC-TiB₂ p/Ti composite was in-situ synthesized on the TC4 alloy surface by using argon arc cladding.The microstructure of the coating was investigated by scanning electron microscope (SEM) and X-ray diffraction (XRD),and the microhardness of the coating was measured.The results show that the main phases in the coating were TiC,TiB₂ and Ti(Ni, Cr),with TiB₂ phases in rod-like form.Excellent bonding between the coating and TC4 substrate occurred without pores or cracking,and fine TiC and TiB₂ particles uniformly distributed in the coating.The microstructure was different from the outside to the inside in the clad coating.The microhardness of coating was 13818MPa,improved about 4.5 times than the TC4 alloy substrate.