Combustion mechanisms of core–shell structured aluminized explosives under oxygen atmosphere: Reactive molecular dynamics simulations

Abstract

We constructed four aluminized explosive nanoparticles (NPs) with core–shell structure, in which the explosives CL-20, HMX, RDX, and TATB serve as a core and the aluminum acts as a shell. The combustion processes of the aluminized explosive NPs under oxygen atmosphere at 2500 K were simulated by reactive molecular dynamics. The Al shells underwent a process of melting-diffusion–reaction-aggregation, which began from the initial surface shell to the block. O2 rarely directly participated in the initial decomposition of the explosive molecules and mainly reacted with the intermediates and free radicals. A large number of the solid aluminized substances generated during the combustion. The AlmOn clusters are the main component of solid aluminized substances, in which the Al and O atoms at the edge will react with C, the H and N atoms, while the AlmCn and AlmNn clusters distributed sporadically. The AlmOn cluster in the TATB@AlO NP has a block structure, while the others have sphere-shaped structures. This work may provide a theoretical basis for understanding the combustion mechanisms of the aluminized explosives.