Abstract：To obtain lead-free glass frits with excellent thermal properties, Bi₂O₃-SiO₂-B₂O₃-ZnO-Al₂O₃ glass powders were prepared by sol-gel method. Morphologies, characteristic temperature, crystallization characteristics, thermal expansion and flexibility of glass were investigated by scanning electron microscopy (SEM) , differential scanning calorimetry (DSC) , X-ray diffraction test analysis (XRD) , thermal expansion instrument and “button” experiments. The connection between these properties was analyzed. The results show that sol-gel glass powders are porous. The ball milled particle size is mainly in0.1~1 μm and glass transition temperature is 485 ℃, the softening temperature is 541 ℃. The glass powder is amorphous in the range of 25~1 000 ℃. The thermal expansion coefficient is 6.57×10^-6℃^-1ranging from 25 to 300 ℃, it presents a good flexibility when firing at 700~725 ℃.

Keywords: sol-gel method; Bi₂O₃-SiO₂-B₂O₃-ZnO-Al₂O₃ glass powders; thermal properties