Effects of binary sintering additives (SmF3-Sm2O3) and sintering temperature on β-SiAlON ceramic tool materials

β-SiAlON ceramic tool materials were fabricated via spark plasma sintering using binary sintering additives (SmF 3 -Sm 2 O 3 ). The effects of SmF 3 addition and sintering temperature on the densification, phase composition, microstructure and mechanical properties were studied. Furthermore, the corrosion behavior of β-SiAlON ceramic tool materials due to excessive SmF 3 at high sintering temperatures (≥1700 °C) was revealed. The results indicated that SmF 3 could promote the densification and generation of β-SiAlON. Higher SmF 3 content and sintering temperature increased the aspect ratio and average grain size of β-SiAlON, which made fracture toughness increase and Vickers hardness decrease. The best density, fracture toughness and hardness of β-SiAlON ceramic tool materials were 3.204 g/cm 3 , 6.45 ± 0.07 MPa m 1/2 and 16.72 ± 0.09 GPa. However, β-SiAlON was corroded by excessive SmF 3 during high temperature sintering, resulting in deterioration in densification and properties.