ABSTRACT
The reaction sintering of powder compacts, in which densification and chemical reaction of the starting powders occur in the same heating cycle, is considered. Results for the ZnO-Fe2O3, ZnO-Al2O3 and CaO-Al2O3 systems indicate that the reaction and any associated volume change are, by themselves, not the dominant factors in the subsequent densification. Instead, the microstructural change produced by the reaction is a major factor in the subsequent densification. The change in the microstructure is itself affected by the mechanism of the chemical reaction. An important advance of the present work is the identification of the relation between the reaction mechanism and the associated volume change and their influence on the subsequent densification. Processes that can be used to modify the microstructural change produced by the reaction and, hence, the subsequent densification, are discussed.
