ReaxFF Molecular Dynamics Simulation of Hydrostaticand Uniaxial Compression of Nitrate Energetic Materials
2020
The
physical and chemical properties of typical nitrate energetic
materials under hydrostatic compression and uniaxial compression were
studied using the ReaxFF/lg force field combined with the molecular
dynamics simulation method. Under hydrostatic compression, the P–V curve and the bulk modulus (B0) obtained using the VFRS equation of state
show that the compressibility of the three crystals is nitroglycerine
(NG) > erythritol tetranitrate (ETN) > 2,3-bis-hydroxymethyl-2,3-dinitro-1,4-butanediol
tetranitrate (NEST-1). The a- and c-axis of ETN are easy to compress under the action of hydrostatic
pressure, but the b-axis is not easy to compress.
The b-axis of NEST-1 is the most compressible, while
the a- and c-axis can be compressed
slightly when the initial pressure increases and then remains unchanged
afterward. The a-, b-, and c-axes of NG all have similar compressibilities. By analyzing
the change trend of the main bond lengths of the crystals, it can
be seen that the most stable of the three crystals is the N–O
bond and the largest change is in the O–NO2 bond.
The stability of the C–O bond shows that the NO3 produced by nitrates is not from the C–O bond fracture. Under
uniaxial compression, the stress tensor component, the average principal
stress, and the hydrostatic pressure have similar trends and amplitudes,
indicating that the anisotropy behaviors of the three crystals ETN,
NEST-1, and NG are weak. There is no significant correlation between
maximum shear stress and sensitivity. The maximum shear stresses τxyand τyz of
the ETN in the [010] direction are 1.5 GPa higher than τxz. However, the maximum shear stress of NG shows
irregularity in different compression directions, indicating that
there is no obvious correlation between the maximum shear stress and
sensitivity.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
55
References
1
Citations
NaN
KQI