Abstract:
Carbon fiber reinforced SiC (C
f/SiC) was successfully vacuum brazed to Ti alloy with (Ti-Zr-Cu-Ni)+W composite filler at 930℃ for 5 min. The interface microstructure was investigated with scanning electron microscope (SEM),energy dispersive spectrometer (EDS) and X-ray diffraction (XRD). The mechanical properties of the brazed joints were measured by mechanical testing machine. The results show that Ti and Zr in the interlayer can react with the C
f/SiC composite, and the brazed seams mainly consist of Ti
3SiC
2,Ti
5Si
3,and some TiC(ZrC) reaction products. The mutual diffusion between Ti from the Ti alloy substrate and Cu and Ni from the interface formed the diffusion-reaction layer between the interlayer and Ti alloy substrate. After heat treating the brazed joint at 900℃ for 60 min,the interlayer microstructure became homogenization and the diffusion layer on TC4 alloy side thickened,and the shear strength of the joint reached 99 MPa,increased 52% comparing with that (65 MPa) before heat treatment.