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.