MACROSCOPIC MODELING OF THE REACTION BONDING OF ALUMINUM-OXIDE

The reaction-bonded aluminum oxide (RBAO) process is a novel method to produce monolithic alumina-based ceramics. In order to gain some insi ght into the process, a macroscopic model, which considers the interac tion of oxygen diffusion and reaction within a porous body, has been d eveloped. The model allows one to predict, to a first approximation, t he effects of parameters, such as heat-treatment cycle, atmosphere, an d scale - an important consideration for industrial applications. Ther mogravimetric (TG) curves predicted by the model show reasonable agree ment with experimental data and indicate that the process is controlle d by a combination of reaction and diffusion. (C) 1997 Elsevier Scienc e Limited.