Self-heating of a polymeric particulate composite under mechanical excitations

A theoretical thermo-viscoelastic model is developed to predict the mechanical and thermal response of a particulate composite beam subject to externally applied excitations. The effective viscoelastic material behavior of a polymeric particulate composite is obtained from the micromechanics-based modeling with the properties of the individual material phases and corresponding volume fractions. The thermo-mechanical response of a particulate composite beam consisting of a viscoelastic polymeric matrix and elastic aluminum particles is modeled under near-resonant excitations through a first-order shear deformable beam theory. To validate the model, particulate composite beams with a 30% volume fraction of the aluminum particles embedded in polydimethylsiloxane matrix were fabricated, and the self-heating behavior of the composite at near-resonant excitation was then investigated. The overall temperature rise at different locations of the composite predicted by the present model agrees well with the experimental measurement. This work provides a very useful platform for the design and development of new energetic materials under a certain loading environment. The present model can also be applied to more general particulate composite materials with different geometries consisting of different particle fillers and polymer matrices.