Abstract: We demonstrate a process to achieve selective surface metallization of ZrO₂ ceramics using ultrasound technology in atmospheric environments at 350 °C, which bestows good weldability of ZrO₂ to achieve rapid and reliable connections with other metals as well as ceramic materials. The challenge is that brazing or diffusion welding processes to accomplish metallurgical connections for ZrO₂ typically require holding at elevated temperatures for minutes to hours, while the selective ultrasonic metallization process requires only a few seconds of processing without the application of covering films or solder resists. In this study, the selected Sn-2Ti alloy could effectively wet and spread on ZrO₂ substrate under ultrasonication, and continuous interphase layers were rapidly formed in situ between ZrO₂ and Sn-2Ti. The bonding strength for the ZrO₂/Sn-2Ti interface was well established with the highest shear strength of 37.1 MPa, and the fracture location occurred at the filler metal. The interfacial reaction layer thickened remarkably with the prolongation of sonication, accompanied by the partial crystallization of amorphous TiO and the formation of irregularly striped Ti_11.31Sn₃O₁₀ nanocrystals.

Key words: Selective ultrasonic metallization, Zirconia surface patterning, Low temperature connection, Sono-oxidation, Interfacial reaction