Abstract
Effects of powder characteristics on the sintering of eight kinds of commercial a-Fe2O3 powders have been studied with special reference to the aggregation state by constant-rate heating method. Techniques used are dilatometry, mercury porosimetry, and photomicroscopy. It is shown that the temperature at which densification starts is well correlated with the primary particle size, while the fired density, with the size ratio of pore to primary particle. A striking difference in the sintering behavior was observed between the powders containing hard aggregated particles and those composed of soft agglomerates. Hard aggregates have deleterious effects not only on the sintering of compacts but also on the microstructure of sintered bodies.
