Measuring absorptivity of ceramic materials at high temperatures in Gyrotron Ceramics Sintering System

摘要

The development of processes based on the mi- crowave heating of materials requires knowledge of the dielectric properties of the materials and their temperature dependences . In this work we measur e the microwave radiation absorption coefficient in alumina -based ceramic materials over a wide range of temperatures. The method is based on comparing the Q-factors of an unloaded resonato r and a resonator with an absorbing sa mple placed inside [1], [2] . In our experiments the working chamber of the gyrotron complex is in fact a multimode (L λ ) untuned reso- nator [3]. A distinctive feature of this method is the use of radiation simultaneously for both diagnosis of properties (measurement of the absorption coefficient) and heating of the sample.