Fabrication of Ceramics with Highly Controlled Microstructures by Advanced Fine Powder Processing

Abstract

Abstract To add new functions and improve the performance of advanced ceramics, highly controlled microstructure is required. The microstructure control of the hierachical, graded, laminated, or oriented microstructures at all levels from micrometer to nanometer order is a well-known example. To satisfy the requirements, advances in powder processing are indispensable (Sakka, 2006). Powder processing consists of the following processes: (1) preparation of particles, (2) surface modification of the particles, (3) consolidation, and (4) sintering. To obtain a fine microstructure after sintering, fine particles should be used as the starting material. However, as the particle size decreases, particles tend to agglomerate easily, leading to a nonuniform structure containing large pores caused by the agglomerates. To address this problem, colloidal processing, in which fine particles are dispersed in a solvent, formed, and consolidated, has been attracting attention (Sakka, 2007).