| Summary: | Vacuum brazing of TiAl alloy and 316L stainless steel (SS) was conducted using Zr-42.9Cu-21.4Ni amorphous filler metal. The effect of brazing temperature and brazing time on the microstructure and shear properties of the dissimilar metal joints between TiAl alloy and 316L stainless steel was investigated. The results show that the interface of the brazed joint can be divided into six different reaction layers. The microstructure of the brazed joints from TiAl alloy to 316L stainless steel at 1040 ℃/10 min is γ(TiAl)+AlCuTi/α2(Ti3Al)+AlCuTi/AlCu+ZrCuNi+FeZr/Cu8Zr3+ZrCuNi+TiFe+Fe2Zr/FeZr+Fe2Zr+TiFe2+ZrCu/α-(Fe, Cr). With the increase of brazing temperature, the shear strength of brazed joints increase first and then decrease. The maximum shear strength of 162 MPa is obtained at 1040 ℃/25 min. Fracture analysis indicates that cracks initiate at the interface of FeZr+Fe2Zr+TiFe2+ZrCu, and then propagate along Cu8Zr3+ZrCuNi+TiFe+Fe2Zr and α-(Fe, Cr) with cleavage fracture pattern.
|
|---|