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arXiv · 1102.3718

Compaction dynamics of metallic nano-foams: A molecular dynamics simulation study

M. A. Duchaineau·J. B. Elliott·A. V. Hamza·T. Dittrich·T. Diaz de la Rubia·Farid F. Abraham
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Abstract

We investigate, by molecular dynamics simulation, the generic features associated with the dynamic compaction of metallic nano-foams at very high strain rates. A universal feature of the dynamic compaction process is revealed as composed of two distinct regions: a growing crushed region and a leading fluid precursor. The crushed region has a density lower than the solid material and gradually grows thicker in time by {\it snowplowing}. The trapped fluid precursor is created by ablation and/or melting of the foam filaments and the subsequent confinement of the hot atoms in a region comparable to the filament length of the foam. Quantitative characterization of nano-foam compaction dynamics is presented and the compacted form equation-of-state is discussed. We argue that high-energy foam crushing is not a shock phenomenon even though both share the snowplow feature.

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M. A. Duchaineau, J. B. Elliott, A. V. Hamza, T. Dittrich, T. Diaz de la Rubia, Farid F. Abraham. 2011-02-17. Compaction dynamics of metallic nano-foams: A molecular dynamics simulation study. https://arxiv.org/abs/1102.3718

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