Benefits of Zr additive element in the Ti 24Ni eutectic filler in vacuum brazing of SiC ceramics

摘要: Abstract The SiC ceramics have been successfully brazed using Ti 24Ni (at. %) eutectic filler at 1030 °C with 15 min holding time. A Ti5Si3 and TiC mixed reaction layer was formed adjacent to substrate, while Ti2Ni intermetallic compound the major component in brazing seam area. It's found that phase has extremely high coefficient of thermal expansion (CTE), residual stress caused by CTE mismatch between is unfavorable for shear strength joints. Through adding 15 at. % Zr into filler, α-Ti[Zr] solid solution lower as well good ductility generated joints, which beneficial relaxing stress. Consequently, joints improved from 69 MPa 112  MPa at room temperature 36 MPa 62  MPa at 600 °C, respectively.