Oxidation Mechanism of Graphene Coating on an Aluminum Slab

Surface engineering is a promising approach to enhance the combustion performance of energetic materials. The carbon-based coating provides several advantages in ignition temperature, processability and compatibility. This work conducted the reactive molecular dynamic simulations on aluminium slabs with graphene coating to elaborate the underlying oxidation mechanisms. The combustion evolution of coated slabs is examined under the flow impact to capture the anisotropic nature in explosion. From the analysis of stress distributions and morphological evolutions, the deformation and disruption mechanisms of bilayer graphene are discussed in detail. Successive surface collisions result in the preferable crack on the lower graphene layer close to the aluminum substrate, rather than the upper layer. Compared with alumina coating, the modified slab exhibits an enhanced heat release due to the better mass diffusion. We further identify the bond populations and oxidation products to elaborate the reaction mechanism and highlight the intense impulse of modified slab. These numerical findings are expected to provide a theoretical guidance for the design of next-generation energetic materials.