Mechanical Behavior of a PBX Substitute Material under Static and Dynamic Loading

A polymer-bonded explosive substitute material (PBX) composed of sugar granules and polymer binder was fabricated with a weight proportion of 90:10. Static Brazilian tests accompanied by high-speed photography, digital image correlation (DIC) technology, and dynamic mechanical analysis (DMA) were carried out. The tensile stress-strain relation is quasi-linear until failure with a tensile strength of about 0.89 MPa, elastic modulus of 35 MPa, and Poisson's ratio of 0.392. Microscopically, interfacial debonding and intergranular fractures are the main mechanisms of damage. By DMA, the storage modulus and tan delta show a strong dependence on temperature and less dependence on frequency; the glass transition temperature is found to be about 50 degrees C. These results are helpful for understanding the behavior of PBX under tensile and dynamic loading.