Impact sensitivity in respect of the crystal lattice free volume and the characteristics of plasticity of some nitramine explosives

The relationship between the crystal lattice free volume, ΔV, and impact sensitivity, E_dr, of ten nitramines has been analyzed. It was found that this relationship is not uniquely determined, i.e. it is not given only by their own ΔV values but fundamentally by the type and intensity of the intermolecular forces in the nitramine crystals. Also, relationships between the E_dr values, on the one hand, and bulk modulus, K, and shear modulus, G, on the other, have been the subject of discussion not only for pure cyclic nitramines but also for their PBXs, bonded by a poly-fluoro binder. The closest linear correlation exists between the E_dr values and dimensionless K·G^-1 ratio which indicates the plasticity range. A similar relationship is valid also for the ΔV values. Relationships of the E_dr and/or ΔV values with the shear modulus or to the K·G^-1 ratio reflect an unusual behavior of ε-HNIW to which the published morphological instability of this particular HNIW version might also be related.