In-situ synthesis of TiC-TiB₂ anti-oxidation composite layer by argon arc cladding

TiC-TiB₂ composite layer was in situ synthesized on the surface of graphite electrode by argon arc cladding technology with Si and B₄C powders as raw materials, in order to improve the high-temperature anti-oxidation property of graphite. The tissue morphology and phase composition were analyzed with scanning electron microscopy, Zeiss electron microscope and X-ray diffraction, respectively. The high temperature anti-oxidation property of TiC-TiB₂ composite layer was examined by intermittent method. The results show that the cladding layer was composed of petal-shaped TiC phase and rod-shaped TiB₂ phase. The cladding layer and graphite substrate had good thermal compatibility, and no defects such as surface cracks or pores happened. The cladding layer had good high-temperature anti-oxidation property. The oxidation rate of weight gains was only 0.546 mg·mm^-2h^-1 after oxidized at 1 300℃ for 6 h.