SiC whisker toughened Al2O3-(Ti, W)C ceramic matrix composites

Al2O3/SiCw ceramic end mill was prepared via spark plasma sintering (SPS). The grain growth kinetics, densification mechanism and effect of SiCw on Al2O3 ceramics were studied. Cutting performance of the Al2O3/SiCw ceramic end mill was evaluated by high-speed machining Inconel 718. The results showed that the densification mechanism of Al2O3 ceramics was dominated by grain boundary diffusion when the sintering temperature was lower than 1500 °C. The Al2O3/SiCw ceramic end mill with a 25 wt% SiCw content, prepared at 1400 °C and the holding time of 5 min, possessed the most optimal mechanical properties. The relative density, Vickers hardness and fracture toughness were 99 ± 0.1%, 21.9 ± 0.8 GPa and 6.9 ± 0.4 MPa m1/2, respectively. The ceramic end mill exhibited satisfactory performance in cutting with Inconel 718 workpieces, and the tool failure was mainly caused by wear.