Preparation of Cu-Fe-Cu Composite Plate with Large Thickness by Explosive Welding

Fe-Cu composite plate has good ductility, electrical and thermal conductivity, the ferromagnetism of Fe, and the diamagnetism of Cu, so it can be widely used in power, electronics and other industries. However, it is hard to weld Fe and Cu using conventional methods due to their low mutual miscibility. In the present study, the explosive welding method was adopted to prepare the Cu-Fe-Cu (with the thickness 17, 5, 17 mm) composite plate. Firstly, the theoretical model was adopted to design explosive welding parameters. The weldability window, the detonation velocity and thickness of the charge, and the gap size were obtained. Then, a new numerical simulation method, in which the SPH (smoothed particle hydrodynamic method), Lagrange and Euler methods are used and no equivalent treatment of the explosive welding components is taken, was used to analyze the explosive welding process. The collision velocity of the flyer plate, temperature and pressure distribution near the bonding interface as well as wavy interface were obtained, and it proved the validity of the theoretical design parameters. Finally, the Cu-Fe-Cu composite plate was successfully prepared by the explosive welding method. The hardness distribution and the shear strength of the bonding interfaces were tested. The results show that parameters of the interface wave obtained experimentally and numerically are basically the same; compared with that of the original ones, the hardness of Fe and Cu near the bonding interface increases by about 34.2% and 49.8%, respectively; the average shear strength of the first and the second interface is 212.7 MPa and 225.3 MPa, respectively.