The mechanical response of TNT and a composite, composition b, of TNT and RDX to compressive stress: I uniaxial stress and fracture

The stress strain behavior, compressive strength and Young's modulus of trinitrotoluene (TNT) and a composite (Composition B) of TNT and cyclotrimethylene trinitramine (RDX) have been investigated in uniaxial compression as a function of temperature and strain rate. The compressive strengths and the moduli decrease with increasing temperature and decreasing strain rate. Limited tensile measurements were also made. Failure is by brittle fracture for all conditions investigated and can be explained in terms of the Griffith criteria for fracture. The temperature and strain rate dependence of the compressive strength can be attributed to the dependence of the modulus on these parameters and thermally activated slow subcritical crack growth before fracture.