Dynamic behavior of additively manufactured particulate composites with topologically tailored microstructure

This study investigates deformation and dynamic behavior of additively manufactured particulate composites with purpose-built microstructural patterns and the effects of microstructural topology on their response under dynamic loading. These composites serve as effective simulators for reactive polymer-bonded explosives. A pressure-assisted binder jet process is employed to fabricate high-density particulate composites with topologically tailored microstructures. Void distribution is controlled through selective incorporation of a void-generation agent in the composite volume, while particle size distribution is adjusted by printing with distinct particles with different sizes. A Split Hopkinson pressure bar (SHPB) test, integrated with a high-speed camera, was used to determine the displacement and strain fields via digital image correlation (DIC). The results reveal that interfaces between mismatched microstructural regions are prone to strain localization and deformation. Furthermore, microstructural topology—including orientations of void and particle patterns—plays a significant role in shear deformation formation at the interfaces.