2004 Volume 41 Issue 10 Pages 730-737
Constrained sintering of a substrate with a sandwich structure, which was the laminated inner-constraining alumina layer between the glass-alumina mixed layers, has been studied. The influence of specific surface area of the particles and porosity of inner constraining particle layer upon sintering shrinkage was investigated. Specific surface area of the alumina powder for the inner constraining particle layer could be changed by grinding and blending two different particle size powders. As for the debinded sheet used with ground alumina powder, the pore distribution was sharp, and the bending strength was proportional to the specific surface area. In the case of inner constraining particle layer used with ground alumina powder, penetration length of molten glass from glass-alumina mixed layers obeyed Kozeney-Carman's equation. On the other hand, as for the debinded sheet with particle size blended powder, the effects of specific surface area on the bending strength and the penetration length of molten glass differed from the results of the grounded one. Sintering shrinkage in X-Y direction of the sandwhich substrate was basically related to the bending strength of debinded alumina powder sheet for inner constraining particle layer in both cases.
