Mechanical Characterization of Energetic Materials

The goal of this program is to develop experimental and diagnostic technologies for characterizing the mechanical response of high explosive materials. It is well known that the prediction of structural integrity depends upon a thorough knowledge of the stresses and strains produced in the structure and the ability of the material to support these stresses and strains without failure under service loads. To achieve this goal, a full characterization of the material under the service loads is a prerequisite for the development of a reliable constitutive model to predict the stress and strain and the integrity of the structure. In this program, experimental and diagnostic techniques are developed to characterize the mechanical behavior of a plastic-bonded explosive stimulant under different strain rates, temperatures, and confining pressures. The loading ranges of strain rate, temperature, and confining pressure considered in this program are 100/sec to 1000/sec, -60oF to 60oF, and up to 40000psi, respectively. In addition, constitutive models are developed and implemented into a finite element computer code and the optimum nondestructive testing techniques to monitor damage initiation and evolution processes in the material for selected loading conditions are determined.