Abstract:
Induction brazing of TiAl to 40Cr under the protection of Ar gas was carried out with Ag-Cu-Ti filler metal. Fracture surface, inter facial microstructures and formation phases of brazed joints were investiga ted by means of scanning electron microscopy, electron probe microanaly sis and X-ray diffraction, and the joint strength was determined by tensile testing method. The results show that Ti(CuAl)
2,Ags,s,TiC form in the brazing seam and the typical interface structure of brazed joints is TiAl/Ti (CuAl)
2+Ag s, s/Ag s, s/TiC/40Cr. The tensile strength and fracture path of the brazed joints change with brazing time. When the joint is brazed at 1 143 K for 0.9 ks, joint tensile strength as high as 298 MPa is obtained and the fracture occurs in the Ti(CuAl)
2 zone.