A method to obtain the impact strength of triple‐base gun propellant is proposed according to strain energy density. Using a drop‐weight impact testing machine, the impact strengths of DAGR125‐21/19 gun propellant at room temperature (20 °C) and low temperature (−40 °C) were studied. In the experiments, there were different impact energies via changing the drop weight or height. The surface images of gun propellants during the impact process were captured using a high‐speed camera. The deformation of DAGR125‐21/19 gun propellant was calculated through digital image correlation method (DICM). After analyzing the surface images and deformation, it was found that there was a good agreement between the maximum of axial nominal strain energy density (ANSED) and initial fracture point. Finally, the impact strength of DAGR125‐21/19 gun propellant was obtained through calculating the strain energy density during the plastic stage between the yield and initial fracture points. Moreover, successive parallel and replication experiment results proved the rationality and feasibility of the proposed method to determine the impact strengths of DAGR125‐21/19 gun propellant at room temperature (20 °C) and low temperature (−40 °C).

中文翻译：

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基于应变能密度的三基火药冲击强度确定方法

根据应变能密度，提出了一种获得三基火药冲击强度的方法。使用落锤冲击试验机，研究了DAGR125-21 / 19火药推进剂在室温（20°C）和低温（−40°C）下的冲击强度。在实验中，通过改变液滴的重量或高度来产生不同的冲击能量。使用高速摄像机捕获了撞击过程中枪支推进剂的表面图像。通过数字图像相关方法（DICM）计算DAGR125-21 / 19枪推进剂的变形。对表面图像和变形进行分析后，发现轴向标称应变能密度（ANSED）的最大值与初始断裂点之间存在良好的一致性。最后，DAGR125-21 / 19推进剂的冲击强度是通过计算塑性阶段在屈服点和初始断裂点之间的应变能密度获得的。此外，连续的并行和复制实验结果证明了该方法在室温（20°C）和低温（−40°C）下确定DAGR125-21 / 19火药推进剂冲击强度的合理性和可行性。