钎料 Zr 含量对 Ti–13Nb–13Zr/ZrO2 钎焊接头界面组织及性能的影响

Achieving a biocompatible joint between titanium alloy and ZrO₂ ceramic is of great significance to extend its application in the biomedical field. In this paper, the joining between Ti-13Nb-13Zr alloy and ZrO₂ ceramics was achieved with Sn-Zr filler metal. The interfacial microstructure and reaction products of TNZ/ZrO₂ joints were analyzed by X-ray diffraction, scanning electron microscopy and energy disperse spectroscopy, and the shear test was carried out to evaluate the mechanical properties of joints. The effect of Zr content on the interfacial microstructure and mechanical properties of the joints was also investigated. The results show that the typical microstructure of the joints brazed at 600 C for 30 min with Sn-6Zr (atomic fraction) filler metal is TNZ/Ti6Sn5/p-Sn+Zr(s,s)+ ZrSn2/m-ZrO₂/ZrO₂. Among all of the reaction phases, the formation of m-ZrO₂ facilitates the metallurgical bonding between ZrO₂ substrate and brazing seam. The amounts of both Zr solid solution and ZrSn2 phase increase, but the proportion of p~Sn in the brazing seam gradually decreases with the increase of Zr content. The maximum average shear strength of brazing joints reaches 25.6 MPa when the Zr content is 6%. According to the analysis of fracture path, the joints brazed with Sn-6Zr mainly fracture along the p~Sn in the brazing seam.