Wetting and sealing of the interface between silicate glass and copper

Abstract

Abstract In order to realize reliable sealing and combining of constructional glass and copper, the effects of temperature, holding time, and roughness on their wetting properties were studied. The contact angle and drop diameter were measured by microscopy. The microstructure, element distribution and chemical composition of the reaction interface were analyzed by scanning electron microscopy and energy dispersive X-ray spectroscopy to reveal the relationship between the contact angle and the reaction interface. The results show that the glass/copper contact angle of the sample tested constantly decreases with increasing temperature. If the holding temperature is increased from 980°C to 990°C, and the wetting angle is reduced from 83.22° to 55.28°. When the holding time is prolonged from 5 min to 40 min at 1000°C, the wetting angle decreases and the size of the black halo around the glass reduces. The copper surface roughness has little effect on the wetting angle. Therefore, during the actual sealing process, increasing the temperature and holding time, could effectively improve the wetting behavior of the glass and copper. The black halo formation and interfacial reaction mechanism are also discussed.