Influence of aluminum alloy interlayers with different composition on bonding strength of high volume fraction aluminum matrix composites

Using the aluminum alloys as the interlayers, the 60%SiC/6061Al composites (volume fraction) were bonded by hot isostatic pressure, the influence of aluminum alloy interlayers with varying composition (without Al, 1060Al, and 4047Al) on the microstructure and bonding strength of the joints were investigated. The results show that, the three types of aluminum alloy interlayers are all subjected to hot isostatic pressing to obtain the composites without pores, obvious delamination, and harmful Al₄C₃ phases. When 4047Al is used as the interlayers, the interlayer thickness is the smallest, with the maximum thickness being only 70 μm, and the maximum flexural strength and shear strength of the composites can reach 413 MPa and 140 MPa, respectively. The fracture modes of composites with the three interlayers are mainly composed of the matrix ductile fracture and the SiC particle fracture. The interface bonding strength between the SiC particles and aluminum alloys is relatively high, and the SiC particles play a good load-bearing role.