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Updated: Apr 30, 2026
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Published on: February 9, 2017
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Anisotropic Hot Spot Formation at a Grain Boundary in Shock-Compressed TATB High Explosive Crystal
Matthew P Kroonblawd1, Nithin Mathew2, Puhan Zhao3,4
1Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, United States.
Summary
Molecular dynamics simulations reveal that grain boundary interfaces in high explosives (HEs) create directional hot spots. This anisotropy in hot spot formation is crucial for understanding detonation initiation in secondary explosives.
Area of Science:
- Materials Science
- Computational Chemistry
- Chemical Engineering
Background:
- Secondary high explosives (HEs) possess microstructures that promote hot spot formation, crucial for detonation initiation.
- The precise role of microstructural interfaces, such as grain boundaries (GBs), in this process is not well understood.
Purpose of the Study:
- To develop and apply advanced computational methods for simulating shock interactions with GBs in secondary HEs.
- To quantify the influence of GB orientation and shock direction on hot spot formation.
Main Methods:
- Extensions to the generalized crystal-cutting method (GCCM) were developed to create molecular dynamics (MD) simulation cells with specific GB orientations.
- MD simulations were performed to analyze shock wave interactions with a GB in TATB (1,3,5-triamino-2,4,6-trinitrobenzene).
Main Results:
- A significant directional dependence (anisotropy) in hot spot formation at the GB was observed.
- Shocks transmitted from the (001) to the (100) grain produced a hot spot, while the reverse transmission did not.
- Anisotropy was attributed to differences in shock-deformation mechanisms, wave structures, shock rise times, and thermal equilibrium re-establishment.
Conclusions:
- The study quantifies the anisotropic behavior of GBs in secondary HEs concerning hot spot formation.
- The developed GCCM extensions enable detailed MD studies of interfacial phenomena in molecular materials.
- Understanding GB anisotropy is key to predicting and controlling detonation initiation in energetic materials.
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