Mechanical and Thermal Properties of β'-Sialon Prepared by a Slip Casting Method

Various mechanical and thermal properties of β'-sialon ceramics, Si_6–zAl_zO_zN_8–z, prepared from aqueous slurries by a slip casting method were investigated as a function of Z values from 0 to 4. In the present study, Si_6–zAl_zO_zN_8–z occurred in the β'-sialon crystalline phase only near Z = 1. The maximum values for bending strength and fracture toughness, 660 MPa and 5.7 MPa·m^1/2, respectively, were obtained at Z = 0.5. The thermal expansion coefficient exhibited its lowest value, 3.4 × 10⁻⁶· T⁻¹ , at Z = 0.5. In view of the present results, β'-sialon, Si_6–zAl_zO_zN_8–z (Z = 0.5–1), prepared by a slip casting method using aqueous slurries could be adopted, with no problem, for refractory parts.