Abstract The TiC/TiB2 composite coating was prepared by laser cladding on titanium alloy surface. The microstructure,
microhardness and wear resistance of TiB2+15%TiC composite coating were analysed by SEM, microhardness
tester and friction and wear equipment respectively. The results show that the upper part of the coating is
mainly composed of coarse TiB2 dendrites and a small amount of white granular TiC/TiB eutectic microstructure,
while the middle part of the coating is mainly composed of rod- like, fine needlelike TiB2 phase and small block
TiC phase. The lower part of the coating is composed of dendritic phase, massive TiB2 phase, large flake TiC phase
and a small amount of minor flake TiAl intermetallic compound. The hardness of the coating (960HV0.2) is about
2.7 times of that of the substrate (350HV0.2). The wear resistance of the coating is improved significantly, and the
coating appears less peeling, slight wear marks and particle debris, and the surface of the substrate is mainly furrow
wear. The wear of the coating is 1.132 mg, 20% of that of the substrate (5.342 mg).
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Received: 08 March 2020
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