Abstract:In this work, the connection between the boron content and the wettability of TiZrNiCu/Ti60 system was studied by sessile drop method of elevating and maintaining isothermal process under vacuum, and TiBw-TC4 composite was successfully brazed to Ti60 alloy using TiZrNiCu-B filler alloy with brazing temperature of 940 °C for 10 min. The contact angle of TiZrNiCu/Ti60 alloy substrate and the corresponding interfacial microstructure, the interfacial microstructures and shear fractures of brazed joints were studied using SEM, EDS and XRD, and the influence of B content on interfacial microstructure and joining properties was also investigated in detail. Added B element can react with Ti to in-situ synthesizing TiB whiskers (TiBw), which resulted in a relative refinement of microstructure. And the maximum shear strength of TiBw-TC4/TiZrNiCu-B/Ti60 joint was 177 MPa when the content of B is 0.3 wt.%, which was 65% higher than the joints brazed without B content. However, the excessive B content worsened the wetting behavior of TiZrNiCu-B on Ti60 alloy substrate, resulted in the microvoids and disconnected area in the brazed joint, and the shear strength decreased inevitably.