HE Yifeng ¹, LI Xiuying ¹, LI Chaoyuan ¹, GUO Huiming ¹, XIAO Zhuohao ¹, ZHU Shengbin ¹, DONG Hongbo ², FU Zhen ³
(1. School of Material Science and Engineering, Jingdezhen Ceramic University, Jingdezhen 333403, Jiangxi, China; 2. Linyi University, Linyi 276005, Shandong, China; 3. Shandong Jingyao Glass Group Co., Ltd., Linyi 276624, Shandong, China)

Abstract: Lead-free low melting glasses, ZnO-CuO-Bi₂O₃-B₂O₃-SiO₂ system, with fixed contents of 15 mol% CuO and 20 mol% Bi₂O₃, were prepared by using melt cooling method. Structure and thermal properties of the glasses were studied by using X-ray diffractometer (XRD), infrared spectrometer (FIT-IR), thermal dilatometer and differential thermal analyzer (DTA). Chemical durability of the glasses was studied by using dissolution rate method. Wettability of glasses on substrate was tested by using button sintering experiment. It is found that alkaline resistance of the glass solders is lower than that of plate glass and the water resistance is comparable with that of plate glass. The sealing temperatures are Ts=445–490 ℃, while the average thermal expansion coefficient from room temperature to 300 ℃ is in the range of (65–82)×10⁻⁷ ℃⁻¹. At sealing temperature, the glass solders have good wettability on plate glass or alumina substrate. They are not crystallized even sintered at the sealing temperature for 30 min. The solder glasses are suitable for sealing plate glass, alumina and other inorganic non-metallic materials.
Key words: bismuth borate glass; solder glasses; wettability; chemical durability; thermal properties