添加硼元素对Ni-25at%Si/Ti600接头组织性能的影响规律

The Ti-Zr-Ni-Cu amorphous brazing filler metal with added boron element was used to braze high temperature titanium alloy and self eutectic silicon nickel alloy, and the effects of boron element content and brazing process on the interface structure and mechanical properties of the joint were explored. The interface structure of Ni-25at%Si/Ti-Zr-Ni-Cu+B amorphous brazing filler metal/Ti600 brazing joints was optimized to obtain higher performance joints. The research results show that by introducing boron element to metallurgically control the brazing process, TiB whiskers were obtained, which can produce compound strengthening effect on the Ti₂Ni layer, significantly reduce the residual stress at the Ti600 side interface of the joint, delay crack, hinder crack propagation of the joint by pull-out strengthening, and thus improve the strength of the joint. The average strength of the Ni-25at%Si/Ti600 brazing joint under the 1 213 K/10 min process conditions was increased to 84 MPa, and there were no cracks and holes inside the joint. Quality of the Si-Ni alloy/high temperature titanium alloy brazing joint was successfully improved.