Under plate impact experiments (uniaxial strain) single crystal explosives exhibit elastic-plastic mechanical behavior, however at quasi-static rates (uniaxial stress) they are brittle. We have conducted Split-Hopkinson Pressure Bar (SHPB) experiments to bridge the strain rate gap between the two extremes in an effort to…
Current understanding of the events leading to high energy localisation in heterogeneous energetic materials (HEMs) remains unclear. This is because the energy associated with the primary initiation mechanism for hot spot formation is difficult to quantify, and the associated local temperature increases challenging to…
Heterogeneous energetic materials often display complex microstructures with numerous defects, such as inclusions, cracks, and interfaces. When shock-compressed to sub-detonative pressures, the hot spots formed in the vicinity of these defects are responsible for triggering chemical reactions. While energy localization associated with intragranular void…
A thermodynamically consistent phase-field (PF) theory for phase transformations (PTs) between three different phases is developed with emphases on the effect of a stress tensor and interface interactions. The phase equilibrium and stability conditions for homogeneous phases are derived and a thermodynamic potential which…
Composite propellant is commonly used to propel civil and military rockets. As a filled elastomer, it presents time-dependent properties and expresses a nonlinear mechanical behavior when submitted to cyclic loads [1]. A constitutive law able to predict these nonlinearities, such as Mullins effect, is…
The heterogeneous, polycrystalline structure of plastic-bonded explosives (PBX) leads to temperature localization under impacts. The thermo-mechanical responses of PBXs span processes from dislocation-mediated plasticity at small-scales to interfacial stress wave reflection and diffusion at higher scales. The thermal and deformation localization responses under impact…
