Effects of processing parameters on microstructure and mechanical behavior of SiO2/Ti-6Al-4V joint brazed with AgCu/Ni interlayer

SiO2 glass ceramic has been successfully joined to Ti-6Al-4V alloy with AgCu/Ni composite interlayer. The brazing temperature varies from 950 °C to 980 °C, with the holding time ranging from 1 min to 45 min. AgCu eutectic foil melted first, followed by the Ti-Cu-Ni ternary eutectic reaction, then Ti reacted to SiO2 glass ceramic. All of Ti atoms came from Ti-6Al-4V alloy but not from braze alloy. The effects of brazing temperature and dwelling time on interface structure and joint strength were investigated in the present work. The largest shear strength of brazed joint could reach 110 MPa when the brazing temperature was 970 °C, holding time was 10 min, and fracture occurred in the SiO2 glass ceramic part. While the thin reaction layer at SiO2 side is the weak part of the joint when the brazing parameter is not appropriate.