Atomic motion behavior calculation and bonding mechanism analysis of explosive welding of high-strength and high-hardness titanium alloy Ti6Al4V/aluminum alloy 7075

Abstract The explosive welding technology of titanium alloy Ti6Al4V/aluminum alloy 7075 is the most valuable research problem in the field of Ti/Al explosive welding. In this paper, the smooth particle hydrodynamics and molecular dynamics algorithms are used to conduct multi-scale numerical calculations on the explosive welding of Ti6Al4V and 7075. The interface morphology, interface atomic movement, lattice changes and crystal defects are comprehensively analyzed. With the calculation as a reference, the Ti6Al4V/7075 composite with a flat interface is prepared. The calculation results indicate that with the transformation of titanium aluminum crystal structure, a large number of various dislocations, mainly 1/6〈110〉dislocations, are generated on the titanium side; During explosive welding, uniform and stable element diffusion occurred. Element diffusion mainly occurred in the unloading stage when the pressure was 0. The melting zone and ablation zone were composed of TiAl and TiAl3, respectively; The fundamental reason for the combination of Ti6Al4V/7075 is the diffusion of elements and the solid-phase binding of atoms.