Sealing performance of tempered vacuum glazing with silver oxide system low melting solder

Abstract In this paper, the safe sealing temperature range of tempered glass was determined to be no more than 300 °C by experiments. On this basis, the feasibility of silver oxide system low melting solder (SOSLMS) used in tempered vacuum glazing (TVG) sealing was explored by sealing strength experiment, scanning electron microscope (SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD) and other test methods. The results of sealing strength experiment showed that the bonding strength of the sealing layer was inversely proportional to the sealing temperature. The bonding strength of the sealing layer in the range of 260 °C–290 °C met the standard requirements (not less than 0.6 MPa) except for the failure of the sample sealing at 300 °C. The observation results of SEM showed that when the sealing temperature was 260 °C and 270 °C, the solder layer had uniform fusion and dense structure, and the sealing layer was tightly bonded. With the increase of sealing temperature, the solder layer began to produce large holes, and there was obvious open gap between solder layer and glass substrate after stretching. The analysis results of EDS showed that the Ag and V elements all diffused into the glass at each sealing temperature, the difference of diffusion concentration and distribution was not significant. The analysis results of XRD showed that when the sealing temperature was in the range of 260 °C–270 °C, there was no crystallization phenomenon in the SOSLMS. When the sealing temperature was in the range of 280 °C–300 °C, Ag2VO2PO4 crystals began to precipitate, and with the increase of temperature, the higher the crystallinity was, the greater the crystal content was. In conclusion, in the range of 260 °C–270 °C, the SOSLMS showed good sealing performance, which was suitable for TVG sealing.