Bonding mechanisms of SiO₂ glass and 1060 Al by ultrasonic assisted active metal soldering process

In this work, the ultrasonic assisted active metal soldering of SiO₂ glass and Al was successfully achieved using Sn-2Ti solder filler at a low soldering temperature of 250 ℃ in ambient atmosphere. A nano-crystalline α-Al₂O₃ layer with the average thickness of 13.9 nm and a nano-crystalline R-TiO₂ layer with the average thickness of 16.2 nm are formed at the interface of Al/Sn and SiO₂/Sn respectively because Al elements did not diffuse from Al alloy side to SiO₂ side, which verified that a sono-oxidation reaction had occurred during the ultrasonic assisted active metal soldering process. The soldered butt joints exhibited an average tensile strength of 25.31 MPa.