Thermal Resistance of Direct Banding Region between Magnesia Ceramics and Copper

抄録

Magnesia ceramic is bonded to copper plate by a direct bonding method. This bonding method is the Refractory Method what has been discovered by the authors. There is a bonding region between the magnesia ceramic and the copper plate. Results of study concerning thermal resistance of the bonding region are described. The thermal resistance is measured by a method which has been invented by the authors. The bonding region is the most stable when the bonding is done at about 1120 °C bonding temperature. Bonding time hardly influences the value of the thermal resistance. A cuprous oxide (CuO) layer exists in the bonding region. Thickness of the CuO layer hardly affects bonding temperature and bonding time. Effective area of the bonding region for heat transfer is measured. The measuring method is based on an ultrasonic flaw detection. Effective thickness of the CuO layer is obtained from a viewpoint of heat transfer. It is found that the thermal resistance is mainly caused by the CuO layer in the bonding region and it mainly depends on the effective area of bonding.