Classical molecular dynamics (CMD) simulation is an important technique for analyzing custom-designed nanostructured materials and nano-sized systems such as nanowires and nanobelts. This research focuses on analyzing the strength of Fe2O3+Al energetic nanocomposites using CMD. A generic potential form is used to describe the behavior of the Fe+Al+Fe2O3+Al2O3 system. The potential is able to describe bulk single crystal behavior of Fe, Al, Fe2O3, Al2O3 as well as interfacial transitions among them. The nanostructures analyzed include polycrystalline Aluminum, Fe2O3 as well as their composites with two different volume fractions (0.6/0.4 and 04/0.6). The polycrystalline structures are generated using voronoi tessellation. Quasi-static strength analyses are carried out using a massively parallel CMD code for both tension and compression. The analyses reveal that reverse Hall-Petch (H-P) effect is operative for polycrystalline Al under both tension and compression. However, for polycrystalline Fe2O3 reverse H-P effect is operative under tension only. Compression still shows direct H-P effect. This effect transcends into the strength of both composites at all grain sizes. In addition, we also observe tension-compression strength asymmetry in the all polycrystalline systems. This framework offers an important tool for nanoscale design of advanced nanocomposite materials.

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