A new partially isostatic method for fast debinding of low-pressure injection molded ceramic parts

Injection molding has many important advantages over other methods for the production of advanced ceramic bodies with complex shapes. However, the particle size has been a limiting factor both in conventional injection molding as well as in low-pressure injection molding (LPIM). Besides that, both low- and high-pressure processes are very often limited to the production of thin ceramic bodies, due to common problems arising in the debinding stage. In this paper, we present a new method for fast debinding of relatively large cross-section ceramic parts (similar to10 mm) with particle size less than 0.5 mum that we call partially isostatic debinding. The green body is embedded in a ceramic powder bed subjected to external pressure. A substantial extraction of the organic additives was achieved in just a few hours. Sintered alumina bodies with large cross section can be obtained free of defects, with little distortion and densities higher than 98% of the theoretical value. (C) 2003 Elsevier Science B.V. All rights reserved.