Wear resistance of silicon infiltrated B4C/BN composites

The B₄C/BN composites were fabricated by hot-pressing process. In this research, the silicon infiltration process was applied to improve the surface hardness and wear resistance of the B₄C/BN composites. The phase composition, microstructure, Vickers hardness and wear resistance of the silicon infiltrated B₄C/BN composites were investigated and compared with the hot-pressed B₄C/BN composites. XRD analysis results of the silicon infiltrated specimens showed that the resultant coating was mainly composed of silicon carbide and silicon. The Vickers hardness of the silicon infiltrated B₄C/BN composites was significantly improved in comparison with the hot-pressed B₄C/BN composites. The Vickers hardness of the silicon infiltrated B₄C/BN composites achieved to 12-16 GPa. The wear resistances of the silicon infiltrated B₄C/BN composites were also significantly improved in comparison with the hot-pressed B₄C/BN composites. SEM micrograph of silicon infiltrated specimens showed that the thickness of silicon carbide and silicon coating was about 200-300 μm, which significantly improved the surface hardness and wear resistance of the B₄C/BN composites.