The Effect of B/Si and CuO on the Structure and Properties of a Novel Heat-Absorbing BZS–CuO Low-Melting Glass Used for Laser Sealing Vacuum Glazing

Abstract

A novel lead-free, heat-absorbing B₂O₃–ZnO–SiO₂–CuO (BZS–CuO) low-melting glass was successfully prepared. The effects of B₂O₃/SiO₂(B/Si) ratio and the content of CuO on the properties and structure of the lead-free, heat-absorbing BZS–CuO low-melting glass were studied. The optimal BZS–CuO low-melting glass component was determined by thermal properties, bending strength, and absorbance. The introduction of CuO makes the glass exhibit excellent endothermic properties. Because Cu²⁺ enhances the absorption capacity of the glass in the near-infrared region, which converts this part of the light energy into heat energy and reduces the heat passing through the glass, thereby improving the heat absorption performance. The sealing solder made from the optimal BZS–CuO low-melting glass was used as a sealant for vacuum glazing by laser sealing. The microstructural evolution of the solder surface at different powers was investigated. The diffusion bonding between BZS–CuO low-melting glass solder and substrate glass was achieved. The results of our research provide an important reference for the technology of vacuum glazing by laser sealing in the future.