Study on interface characteristics of TC4/7075 explosive welding based on molecular dynamics algorithm

The preparation of TC4/7075 composites for ultra-thin flyer plates is a significant challenge in the field of explosive welding. A weldability window for multi-layer metal explosive welding and a configuration for ultra-thin flyer plate explosive welding were established in this study. TC4/7075 composite materials were successfully prepared with a flyer plate thickness of only 0.3 mm. An analysis was conducted on the material bonding ability, element diffusion, crystal evolution, and microscopic morphology during the explosive welding process of TC4/7075, utilizing the weldability window, molecular dynamics algorithm, and electron backscattered diffraction testing. The results show that various dislocations are present at the interface, predominantly 1/6 ⟨112⟩ dislocations. Element diffusion primarily occurs during the unloading stage at high temperature and zero external pressure; the interface has the best bonding ability when titanium exhibits FCC lattice structure. The prepared composite material demonstrates high intra-grain and grain boundary stresses; the rolling texture is observed on the aluminum side while an equiaxed twin structure forms on the titanium side due to interactions between stacking faults, Stair-rod dislocations, and Hirth immovable dislocations.