Low temperature brazing of biomedical titanium and zirconia metallized with Sn-Ti metal foil

Zirconia ceramic and titanium have been applied more and more extensively in biomedical fields. In this work, reliable brazed joints of ZrO2/Sn-3Ti/AuSn20/Ti were achieved by pre-metallized ZrO2 using biocompatible Sn-3Ti foil. The interfacial microstructures and mechanical properties of the joints brazed at different brazing temperatures for different holding times were fully investigated. The typical interfacial microstructure of ZrO2/Sn-3Ti/AuSn20/Ti joint was ZrO2/Ti2O3 + Ti11.3Sn3O10/ β-Sn + Ti6Sn5 + Ti3Sn + AuSn2 + AuSn4 + massive AuTi5Sn3/layered AuTi5Sn3/Ti. The brazing temperatures and holding times had great influences on the type, quantity and morphology of the intermetallic compounds (IMCs) in the joints. The main phase on the interface transformed from AuSn2 to AuSn4 and IMCs gradually agglomerated and grew up. Besides, the thickness of layered AuTi5Sn3 increased. The optimal shear strength of ∼48.6 MPa was obtained at 550 °C for 30 min. The joint cracked at Ti2O3 layer on the ZrO2 side and extended along the AuSn2 phase and the massive AuTi5Sn3 phase.