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Titanium matrix composite coatings were fabricated on Ti-6A1-4V substrate by laser cladding using powder mixtures of Ti+Cr3C2 and Ti+TiB2, respectively. The chemical compositions and mi-crostructures of the coatings were analyzed using scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and X-ray diffraction (XRD). Microhardness was measured by a microhardness tester. The results showed that Cr3C2 particles were dissolved and deposited to form dendritic TiC in the upper section and spherical grain TiC in the bottom of Cr3C2+Ti coating. Most of TiB2 was dissolved in the molten pool by laser irradiation, then formed TiB with fine needles and coarse needles in the TiB2+Ti coating. A few quasi-melted TiB2 particles with irregular shape at the bottom of the coating were observed. The average microhardnesses were approximately HV850-V1000, HV800-V1050 in the Cr3C2+Ti and TiB2+Ti coating, respectively, which were 2-3 times higher than that of Ti-6A1-4V substrate.
Titanium matrix composite coatings were fabricated on Ti-6A1-4V substrate by laser cladding using powder mixtures of Ti + Cr3C2 and Ti + TiB2, respectively. The chemical compositions and mi-crostructures of the coatings were analyzed using a scanning electron microscope (SEM) Energy dispersive spectrometer (EDS) and X-ray diffraction (XRD). Microhardness was measured by a microhardness tester. The results showed that Cr3C2 particles were dissolved and deposited to form dendritic TiC in the upper section and spherical grain TiC in the bottom of Cr3C2 + Ti coating. Most of TiB2 was dissolved in the molten pool by laser irradiation, then formed TiB with fine needles and coarse needles in the TiB2 + Ti coating. A few quasi-melted TiB2 particles with irregular shape at the bottom of the coating were observed. The average microhardnesses were approximately HV850-V1000, HV800-V1050 in the Cr3C2 + Ti and TiB2 + Ti coatings, respectively, which were 2-3 times higher than that of Ti-6A1-4V substrates.