QIN Ying, LUO Linghong, LIU Liangguang, WANG Leying, CHENG Liang, XU Xu, WU Yefan
(Jiangxi Provincial Key Laboratory of Fuel Cell Material and Devices, Jingdezhen Ceramic Institute, Jingdezhen 333001, Jiangxi, China)
Abstract: The BaO-CaO-Al2O3-B2O3-SiO2 sealing glass was successfully prepared by the traditional process and the glass properties were optimized by improving the melting process. The three process conditions were: 1300 ℃ for 1 h (process A), 1400 °C for 1 h (process B) and 1400 ℃ for 3 h (process C), and samples A, B and C were obtained respectively. The test methods of thermal expansion coefficient, viscosity, and high temperature microscope were used to compare and analyze the performance changes of the three samples. The results show that the thermal expansion coefficient of sample B at 20-558 °C was 10.3 × 10-6 K-1. The viscosity value of the glass sample B at the sealing temperature (850 ℃) was 107.5 dPa·s and it was within the required range of the sealing material (106-109 dPa·s). The wetting angle of sample B also indicates that it can seal the electrolyte well under appropriate pressure. The characterization by the scanning electron microscopy (SEM) and energy dispersivespectrometer (EDS) of the interfacial bonding between glass sample B and YSZ at 750 ℃ for 100 h found that the interfacial bonding performance was excellent and there was no obvious elemental diffusion. Overall, the performance of Sample B is most consistent with the application requirements of the sealing glass material.
Key words: synthesis process; thermal expansion coefficient; viscosity; contact angle; sealing