Evaluation of corrosion-resistant TA9/ZrO2 joint brazed with AuSn20 and Sn-6Zr fillers: Interfacial evolution and mechanical properties

The TA9/ZrO2 joint with outstanding corrosion resistance was obtained by using Sn-6Zr filler metallized ZrO2 ceramics and AuSn20 foils for joining the pre-metallized ceramics and titanium alloy together, providing a new technique to manufacture the packaging shells for implantable devices. Typical interfacial microstructures of the metallization layer and TA9/ZrO2 joint were thoroughly determined. The influence of the brazing parameters on the interfacial microstructure, mechanical properties, and fracture path of the TA9/ZrO2 joint have been sys-tematically studied. Both brazing temperature and holding time have a significant effect on the phase size and distribution of AuTi5Sn3, AuSn4, and AuSn2 phases. The maximum shear strength of the TA9/ZrO2 joint achieved at 550 degrees C for 30 min is 46.5 MPa. Meanwhile, its corrosion resistance is slightly lower than that of the TA9 substrate, and the dense passivation film developed on the joint's surface by the adsorption of corrosion products the interior metal.