A microstructure-based model considering particle distribution, coated level and interface damage for highly-filled composite energetic materials

A microstructure-based model considering the coupling between particle distribution, coated level of particles and binder-particle interface damage-debonding for highly-filled energetic composite materials (HECM) is developed to predict the macro-microscopic mechanical behavior of HECM. A coated parameter rescaling the initial volume fraction of particle relative to binder is imported to describe the significant effects of initially scarce additives on mechanical behavior of HECM. The macroscopic deformation of typical HMX and TATB-based high explosives under uniaxial strain are characterized by three distinct stages: elastic deformation (stage I), stress deterioration due to interface damage (stage II) and fracture (stage III). Parametric studies on microstructural features (particle size and volume fraction, coated level, modulus mismatch) and interface properties (elasticity, strength) underscore their profound influence on macroscopic behavior. Enhanced interface elasticity and strength improve elastic modulus and delay damage initiation, respectively. Smaller particles improve damage resistance, while larger particles dictate fracture dynamics. This research provides critical insights for tailoring HECM performance through microstructural design, interface engineering, and particle size optimization, ultimately advancing the development of robust HECMs with controlled mechanical responses.