Development of α-β SiAlON ceramics from different Si ₃N₄ starting powders

α-β SiAlON ceramics were produced from different starting Si₃N₄ powders including P-Si₃N₄ and α-Si₃N₄ powders and mixtures of these powders. Gas pressure sintering was used for sintering. After sintering, resultant fracture toughness values were correlated with microstructure and starting powders. By optimizing chemistry and process parameters; α-β SiAlON ceramics with reasonable fracture toughness can be produced from rather coarse β-Si ₃N₄ powder. This could improve the economic viability of SiAlON ceramics since β-Si₃N₄ powders are less costly.