Combustion joining of carbon–carbon composites to TiAl intermetallics using a Ti–Al–C powder composite interlayer

To meet the requirements of energy-efficiency and high-quality joining between C/C composites and TiAl intermetallics in the aerospace field, a novel combustion joining method was developed for joining these two materials. In this method, a composite interlayer that consisted of a Ti–Al–C powder mixture and an Ag–Cu–Ti filler foil was employed. The effect of the reactant compositions and preheating temperature on the adiabatic temperature was calculated. Based on the calculated results, the composition of the Ti–Al–C reactants was selected. The joint microstructure was characterized using scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and X-ray diffraction (XRD). The results showed the presence of a TiC layer on the carbon–carbon composite side and Ti–Al–Cu layers on the TiAl side. The shear strength of the joint was tested to evaluate the joint quality. The joint strength reached a maximum value of 17.6 MPa when the interlayer thickness was 500 μm and m = 1.1.