The Characterization of Porous Sintered Reaction-Bonded Silicon Nitride Ceramics Fabricated by Si-Additive Mixture Granules

摘要

Porous sintered reaction-bonded silicon nitride ceramics with dual-sized pore channels were fabricated using granules consisting of a Si-additive. A pressureless tapping method was used to maintain the spherical morphology of the weak spray-dried granules. Emphasis was placed on the formation of wide pore channels (φ ≥ 10 μm). In addition to the successful formation of wide pore channels between the granules, narrow channels formed inside the granules. The size of the wide channels (φ = 5-20 μm) depended on the granule. On the other hand, the narrow channel size (φ< 1 μm) remained the same regardless of the granule size.