Macroscopic modelling 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 insight into the process, a macroscopic model, which considers the interaction of oxygen diffusion and reaction within a porous body, has been developed. The model allows one to predict, to a first approximation, the effects of parameters, such as heat-treatment cycle, atmosphere, and scale - an important consideration for industrial applications. Thermogravimetric (TG) curves predicted by the model show reasonable agreement with experimental data and indicate that the process is controlled by a combination of reaction and diffusion. (C) 1997 Elsevier Science Limited.