IN-SITU MONITORING OF THE SINTERING BEHAVIOR OF MICROCOMPOSITE PARTICLES USING A LASER-SCANNING MICROMETER

The densification behavior of silica-coated alumina particles was inve stigated during sintering using a laser scanning micrometer. Tradition al dilatometric techniques require contact between a push-rod and the sample under study and thus place the sample under stress during the t est. However, the utilization of a noncontact laser micrometer to meas ure dimensional changes during sintering enabled the densification beh avior to be very accurately characterized under a stress-free conditio n. Thus higher temperature experiments, where densification rates are particularly temperature sensitive and the samples are especially soft , can be reliably investigated without the disturbing influence of an external force. The present paper describes an application of the tech nique to evaluate the densification behavior from 900-1300 degrees C o f silica-coated alumina microcomposite particles used for the fabricat ion of mullite.