Characteristics of Large Pores in Green Body Prepared with Floc-Casting Method.

Abstract

Floc-casting method was investigated for fabricating green body free from large pores. Floc-casting method is a consolidation-forming method based on a flocculation phenomenon in concentrated slurry induced by temperature change. A merit of this method is ease to make homogeneous structure. However, the bubble in the slurry remained as large pores in the green body even with de-airing in vacuum. The large pores was quantitatively investigated in green body with optical and confocal laser fluorescent microscope. The green body was made from slurries with various powder contents. The porosity of slurry was measured from weight and volume of slurry before and after de-airing. The porosity of slurry was about 0.5-1.5vol% and increased with increasing powder content. In consolidated body, the pore size in the body increased with increasing powder content in the slurry. The shape of pore was spherical and its size was several hundreds micrometer in diameter.