Calorimetric Measurement of Dielectric Losses in Solids

A new transient calorimetric method for measurement of dielectric losses in solids at 10,000 volts and 1,000 kilocycles, is described in this paper and experimental data obtained by this method are presented. A steady-state method also is described and a direct comparison between the results obtained by the 2 methods is given. The absolute value of loss factor (0.0009) determined for quartz shows exact agreement between the 2 methods. The transient method is shown to reduce the time or making calorimetric measurements on solid materials from hours to minutes. Results of tests on 15 samples, including 6 different low-loss materials, show that the absolute values of losses in these particular materials are of the order of magnitude determined by previous low-voltage high-frequency measurements. It is thought that the transient calorimeter technique can be readily extended to ultra-high frequencies.