Fabrication of Highly Structure Controlled Ceramics by Advanced Powder Processing

Abstract

Highly structure controlled ceramics were required for improving their properties. Powder processing using fine particles provides this required control mechanism through advancement of (1) fine particle preparation, (2) surface modification, (3) consolidation, and (4) sintering. Here some elementary techniques are shown such as colloidal processing for preparing fine-grained dense or porous ceramics, texture control using a strong magnetic field, and simulation of electric current activated/assisted sintering (ECAS). As the developments of the above fine powder processing the following advanced ceramics have been demonstrated. (i) Conductive CNT dispersed alumina with excellent mechanical properties by hetero-coagulation of CNT and alumina powders followed by ECAS, (ii) Ordered porous body with controlled pore size and porosity by hetero- coagulation of burnable polymer and ceramic fine particles, (iii) Shell-like structure (nacre) of MAX phase ceramics with excellent mechanical properties by colloidal processing under strong magnetic field, (iv) Crystalline-textured laminated composite by EPD under strong magnetic field.