The compressive mechanical behavior of composite modified double base (CMDB) propellant was investigated across a wide scope of strain rates ranging from 10⁻³ s⁻¹ to 4210 s⁻¹ at room temperature, by applying a conventional universal testing machine and a split Hopkinson tension bar (SHPB), respectively. The derived stress-strain curves at different strain rates show a strong rate dependence, indicated that yield stress, ultimate stress and strain energy density of CMDB propellant all increase with strain rate by following a power law function, while the amplification of increase are different. The deformation and damage modes of CMDB propellant has changed from a typical ductile manner (cracking along the axial direction) to a brittle manner (maximum shear failure) with increasing of strain rate. Scanning electron microscopy (SEM) was employed to explore the microscopic failure characteristics of CMDB propellant. Under quasi-static loading, the nearly parallel micro-cracks propagating along the axial direction and the debonding of RDX particle without particle crushing can be observed. While under dynamic loading, the micro-crack is 45° angle to the axial direction, and multiple cracking modes of RDX particles appeared. Finally, the correlation between strain energy density and failure mechanisms of CMDB propellant was revealed by developing four characteristic failure modes. The findings of this study is very important to evaluate the structural integrity of CMDB propellant.

^{在从 10 -3} s ^-1到 4210 s ^-1的广泛应变率范围内研究了复合改性双基 (CMDB) 推进剂的压缩力学行为 在室温下，分别应用传统的万能试验机和分离式霍普金森拉杆 (SHPB)。得到的不同应变率下的应力-应变曲线表现出很强的率依赖性，表明CMDB推进剂的屈服应力、极限应力和应变能密度均随应变率的增加而服从幂律函数，而增加的放大倍数不同。随着应变率的增加，CMDB推进剂的变形和破坏方式由典型的延性方式（沿轴向开裂）转变为脆性方式（最大剪切破坏）。采用扫描电子显微镜 (SEM) 探索 CMDB 推进剂的微观失效特征。在准静态载荷下，可以观察到沿轴向扩展的几乎平行的微裂纹和RDX颗粒的脱粘，而没有颗粒破碎。在动载荷作用下，微裂纹与轴向呈45°角，RDX颗粒出现多种开裂模式。最后，通过开发四种特征失效模式，揭示了 CMDB 推进剂的应变能密度与失效机制之间的相关性。这项研究的结果对于评估CMDB推进剂的结构完整性非常重要。通过开发四种特征失效模式，揭示了 CMDB 推进剂的应变能密度与失效机制之间的相关性。这项研究的结果对于评估CMDB推进剂的结构完整性非常重要。通过开发四种特征失效模式，揭示了 CMDB 推进剂的应变能密度与失效机制之间的相关性。这项研究的结果对于评估CMDB推进剂的结构完整性非常重要。