<p>The TC4/Al6061 explosive welding clad plates, which exhibit high strength and impact resistance, can be used for the manufacturing of lightweight armor plates. However, the fabrication of high-quality TC4/Al6061 clad plates is a particularly challenge. To enhance the quality of the TC4/Al6061 clad plates, a coupled SPH-FEM approach, combining the advantages of FEM meshes and SPH particles, was employed to perform macroscopic three-dimensional simulations of the entire explosive welding process. The technology parameters of the explosive welding were determined through the numerical simulations and theory calculation. The unstable detonation region and the rarefaction waves can be captured based on the distribution of the detonation pressure. The issues of edge tensile fracture and unbonded areas in clad plates were effectively addressed by the addition of extension plates. Furthermore, the microscopic morphology of the interface wave was accurately presented by the SPH-FEM simulations. The effectiveness of the explosive welding technology parameters was also verified through the shape and scale of interface waves. The results indicate that the SPH-FEM is an effective means of simulating the processes of detonation, plastic deformation, interface wave formation, and the optimization of the technology parameters for the explosive welding of TC4/Al6061. The simulated interface wave morphology, wavelength, and waveform demonstrate a high degree of consistency with experimental data, with a maximum error of 4.9%. The shear strength of the composite interface exceeds 321.5&#xa0;MPa, and the bonded rate of the clad plates is greater than 95%.</p>