Laser-induced combustion joining of C_f/Al composites and TC4 alloy

The C_f/Al composites were joined to the TC4 alloy via the laser-induced combustion joining method. The exothermic reaction of the interlayer provided the required energy for the joining process. By combining the theoretical calculation and experiment, the chemical composition of the Ni–Al–Zr interlayer was designed. The microstructure and mechanical properties of the joint were investigated. The results show that the addition of Zr slightly weakened the combustion reaction of exothermic interlayer but played a key role in the successful joining. Ni–Al–Zr interlayer reacted with substrates, forming a TiAl₃ layer adjacent to TC4 alloy and NiAl₃, Ni₂Al₃ layers adjacent to the C_f/Al composites. Zr content dominated the microstructure and shear strength of the joint. When the Zr content was 5 wt.% under the joining pressure of 2 MPa, the joint had a maximum shear strength of 19.8 MPa.