Microstructure and properties of vacuum brazing interface of TiB_w/TA15 titanium matrix composites

TiB_w/TA15 titanium matrix composites were vacuum brazed by Ti-Zr-Cu-Ni brazing filler metals, and the microstructure and mechanical properties of the brazed interface were analyzed with different process parameters. The results show that the brazed interface was mainly composed of acicular α-Ti phase, interstitial β-Ti phase, Ti₂(Cu,Ni) intermetallic compounds and TiB_w reinforcing phase. With the increase of brazing temperature (920 ~ 980 ℃) and holding time (60 ~ 150 min), the proportion of acicular α-Ti phase increased, the intermetallic compounds decreased, and the distribution of TiB_w tends to be uniform, and the mechanical properties of the joint increase. However, longer holding time will lead to the increase of brazing interface width and the decrease of joint plasticity. When the amount of filler metal is small and appropriate, brazing temperature 980 ℃, holding time 90 min can obtain the best mechanical properties, maintain good elongation after fracture.