Contactless Monitoring of Shrinkage and Temperature Distribution during Hybrid Microwave Sintering

Abstract

International audienceA novel method to investigate the microwave hybrid sintering process is presented. The method described measures simultaneously over time the changes in shrinkage and temperature field on the sample's surface. The measurements are carried out continuously by using a CCD camera and an IR pyrometer during microwave heating. Moreover, the equipment used is both contactless and less expensive than conventional approaches

Development of an instrumented and automated single mode cavity for ceramic microwave sintering: Application to an alpha pure alumina powder

“…Different setups for dilatometry measurement in microwave cavities were reported in the literature, but for high temperature experiments, optical dilatometry appears to be the best solution. In this study, an optical dilatometry device was thus developed for the single mode microwave cavity, based on the technique developed by Zymelka et al [14] for a multimode cavity.…”

“…Pictures are analyzed using a program developed by Zymelka et al [14] at Ecole des Mines de Saint Etienne, which performs automatic edge detection and diameter measurement for each picture. Diameter changes are finally transformed in densification curves.…”

“…A calibration method based on the melting point of a metal [14,15] was used. This in situ protocol is performed directly in the microwave furnace and in the real microwave sintering conditions.…”

“…However pyrometric measurement requires a calibration procedure, which can be tricky in the case of a microwave oven. Different methods, such as optical dilatometry or telemetry [14][15][16], have been proposed to measure specimen shrinkage.…”

Materials with required dielectric properties: Computational development and production of polymer‐ceramic composites

“…Microwave power engineering is a field in which dielectric materials and their properties play a particularly crucial role. With the development and innovations in the related technologies currently on the rise (see, e.g., ), the designers of systems for different applications continue to struggle with an intrinsic non‐uniformity of microwave heating . Among many methods aiming to homogenize the process, there is a group of techniques attempting to improve the heating profile through a deformation of the pattern of the electric field by partially filling the cavity with appropriate dielectric slabs (e.g., ).…”