The formation process and influencing factors of electric field-induced oxygen vacancy in Y2O3 transparent ceramic

Oxygen vacancy is the key contributing to the rapid bonding in flash joining. Prior to this study, the specific formation process of oxygen vacancy and its influencing factors have not been systematically investigated. In this work, the based materials yttrium oxide and Ti are phased observed during the incubation stage and the flash stage of flash joining. Three periods are summarized to reveal the whole process and variation in oxygen vacancy generation, electron binding, and metal filling. Following the stable stage, the factors impacting the oxygen vacancy are systematically studied and characterized to quantify their contribution. These factors include bonding temperature, current density, joining time, furnace atmosphere, and electric field direction. These findings have significant implications for precisely controlling the strength of the transparent/metal flash joint, meanwhile, may have reference value for universal flash joining.