Cost-effective fabrication of porous α-SiAlON bonded β-SiAlON ceramics

Porous sialon ceramics have been cost-effectively prepared by pressureless sintering from a mixture of elongated SHS β-sialon powders with an α-sialon precursor composition composed of α-Si3N4, AlN, Y2O3 and Al2O3. The obtained porous sialon ceramics exhibited low shrinkage and homogeneous pore size distribution. The results of X-ray diffraction and scanning electron microscopy showed that a uniform microstructure with elongated and intermingled β-SiAlON grains, which were strongly connected by α-SiAlON phase, has been obtained.