Effect of SrO content on microstructure of Bi₂O₃-B₂O₃-ZnO-BaO-SrO low-meltingglass frit and joining performance of sodalime glass substrates

We studied the feasibility of using Bi-based lead-free glass paste as bonding material on soda-lime glass substrates, without any activation preparation on the bonding surfaces. In order to fabricate Bi₂O₃-B₂O₃-ZnO-BaO-SrO system low-melting glass frit, quenching is performed using deionized water after melting using a muffle furnace. Glass paste consisting of glass frit mixed with organic solvent is deposited on the surface of the soda-lime glass substrate by screen printing, and the sealing of the glass substrate is finally achieved at the bonding temperature (500 °C). we discuss the properties of glass powder, the joint microstructure of irregular amorphous glass, the shear properties and the glass frit bonding mechanism based on the characterization results of DSC, XRD, FTIR, Raman, XPS, SEM and TEM. Furthermore, the investigation concentrated on mechanical properties and microstructural characterization of the joined area with two silica substrates. As the SrO content increased from 0 to 3 mol%, T_g increased from 396 °C to 418 °C with increasing SrO content. Accompanied by an increase in SrO content from 1 mol% to 2 mol%, the room-temperature shear strength of the glass specimens increased from 28.5 to 45 MPa. The growth of Bi₂₄B₂O₃₉ crystallites precipitated at the interface was studied.