基于同步光源的含HMX 颗粒HTPB 基体动态 压缩研究

Addressing the unclear mesoscopic damage mechanisms of composite energetic materials under lowvelocity impact, dynamic compression experiments are conducted on HTPB binder specimens containing single/double HMX particles at high strain rates (7 000 s^-1 to 11 000 s^-1) using synchrotron X-ray phase-contrast imaging combined with a modified split-Hopkinson pressure bar (SHPB) system. The mechanical response and mesoscopic damage evolution behavior of these specimens under dynamic compression are systematically analyzed, including the effects of strain rate and particle quantity on damage evolution. Results demonstrate that the overall mechanical behavior of the specimens is dominated by the damage state of HMX particles. During compression, transverse crack initiation and propagation within particles lead to fragmentation, reducing specimen modulus. It is observed that as the strain rate increases, the number of internal cracks within the particles decreases, and the particle response becomes more rapid. Compared to single-particle specimens, double-particle specimens exhibit an increased number of internal particle cracks and demonstrate a more distinct linear segmentation in their stress-strain relationships. The experimental findings reveal that matrix cracking and particle fracture are the primary failure mechanisms of the specimens. Furthermore, higher strain rates and mutual extrusion effects between particles exacerbate the degree of specimen damage. All descriptions adhere to third-person general present tense passive voice, avoid first-person references, and maintain technical consistency throughout.