Vacuum brazing of biomedical TNZ alloy to ZrO₂ ceramic using Sn–Zr filler: interfacial microstructure and mechanical properties

The Sn–Zr filler metal is developed to braze Ti–13Nb–13Zr (TNZ) alloy and ZrO₂ ceramic for biomedical field. The impact of brazing processing parameters on the interfacial microstructure as well as mechanical properties is comprehensively examined and discussed. The typical interfacial microstructure of the joints is TNZ/Ti₆Sn₅/Ti₆Sn₅ + ZrSn₂ + β-Sn/m-ZrO₂/t-ZrO₂, which is obtained at 700 °C for 30 min. Zr active element contributes to the metallurgical bonding between brazing seam and ZrO₂ substrate. As the brazing temperature and holding time increase, there is a rise in the quantity of Ti₆Sn₅ phase and m-ZrO₂, while the content of ZrSn₂ phase declines. The brazed joints exhibit an optimum shear strength of 38.8 MPa when joints are brazed at 700 °C/30 min. The amount of ZrSn₂ phase and m-ZrO₂ has a powerful influence on mechanical properties of joints.