Glass-ceramic composites consisting of 10SrO·50ZnO·40P2O5 (SZP) glass and Al2O3 with various particle sizes and specific surface areas were fabricated for the barrier-rib of plasma display panel. The variations of density, microstructure, bending strength and thermal expansion coefficient with Al2O3 contents were studied for SZP/Al2O3 composites. The positively or negatively charged surface state of SZP and Al2O3 particles was estimated from the pH of the aqueous suspensions prepared using the mixture of SZP glass or Al2O3 particles with 10 vol% and distilled water with pH 7 without pH adjustment. The combination of SZP glass and Al2O3 raw materials with similar charged surface state provides a dense SZP/Al2O3 sintered composite with a relatively-high bending strength and with a homogeneous microstructure.
