LIANG Huayin ¹, WU Shuangchen ¹, YI Weimin ², XIAO Qiankun ¹, WANG Yunzhi ¹, LUO Minhua 1, XIAO Zhuohao 1
(1. School of Materials Science and Engineering, Jingdezhen Ceramic Institute, Jingdezhen 333403, Jiangxi, China; 2. Jiangxi Guanyi Abrasives Co., Ltd., Fengxin 330700, Jiangxi, China)

Abstract: ZnO-Bi₂O₃-B₂O₃ low melting point glasses were prepared by conventional melt quenching method. The influence of nucleating agents TiO₂ and ZrO₂ on the glass ceramic thermal properties and crystallization properties were discussed. The heat treatment effect on the phase composition and microstructure of the glass ceramics were studied. Research shows that TiO₂ or ZrO₂ doped as a nucleating agent separately doesn’t work in ZnO-Bi₂O₃-B₂O₃ glass, while TiO₂ and ZrO₂ co-doped as a nucleating agent can significantly promote crystallization. ZnO-Bi₂O₃-B₂O₃ glass-ceramics are crystallized when the treating temperature arrives at 500°C; the main crystal phases are BiB₃O₆ and BaB₃O₆. The CTE increases with the crystallization time, while the bend strength increases first and then decreases. When the heat-treating condition is set at 500 ℃ for 1.0 h, a glass-ceramic with the CTE of 12.59×10-6 ℃ ^-1 and the bend strength of 57 MPa is obtained.
Key words: nucleating agent, glass-ceramics; sealing glasses; coefficient of thermal expansion