ABSTRACT
PURPOSE: In this study, brazing characteristics of ZrO2 and Ti-6Al-4V brazed joints with increasing temperature were investigated. MATERIALS AND METHODS: The sample size of the ZrO2 was 3 mm x 3 mm x 3 mm (thickness), and Ti-6Al-4V was 10 mm (diameter) x 5 mm (thickness). The filler metal consisted of Ag-Cu-Sn-Ti was prepared in powder form. The brazing sample was heated in a vacuum furnace under 5 x 10(-6) torr atmosphere, while the brazing temperature was changed from 700 to 800degrees C for 30 min. RESULTS: The experimental results shows that brazed joint of ZrO2 and Ti-6Al-4V occurred at 700 - 800degrees C. Brazed joint consisted of Ag-rich matrix and Cu-rich phase. A Cu-Ti intermetallic compounds and a Ti-Sn-Cu-Ag alloy were produced along the Ti-6Al-4V bonded interface. Thickness of the reacted layer along the Ti-6Al-4V bonded interface was increased with brazing temperature. Defect ratios of ZrO2 and Ti-6Al-4V bonded interfaces decreased with brazing temperature. CONCLUSION: Thickness and defect ratio of brazed joints were decreased with increasing temperature. Zirconia was not wetting with filler metal, because the reaction between ZrO2 and Ti did not occur enough.