Zhu Wei, Li Weihang, Li Wenbin, Wang Xiaoming, Yao Wenjin
School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
Polymers (Basel). 2025 Aug 26;17(17):2309. doi: 10.3390/polym17172309.
Tungsten powder/polytetrafluoroethylene (W/PTFE) composites have the potential to replace traditional metallic materials as casings for controllable power warheads. Under explosive loading, they generate high-density and relatively uniformly distributed metal powder particles, thereby enhancing close-range impact effects while reducing collateral damage. To characterize the material's response under impact loading, plate impact tests were conducted to investigate the effects of tungsten content (70 wt%, 80 wt%, and 90 wt%) and tungsten particle size (200 μm, 400 μm, and 600 μm) on the impact behavior of the composites. The free surface velocity histories of the target plates were measured using a 37 mm single-stage light gas gun and a full-fiber laser interferometer (DISAR), enabling the determination of the shock velocity-particle velocity relationship to establish the equation of state. Experimental data show a linear relationship between shock velocity and particle velocity, with the 80 wt% and 90 wt% composites exhibiting similar shock velocities. The fitted slope increases from 2.792 to 2.957 as the tungsten mass fraction rises from 70 wt% to 90 wt%. With particle size increasing from 200 μm to 600 μm, the slope decreases from 3.204 to 2.756, while increases from 224.7 to 633.3. Comparison of the Hugoniot pressure curves of different specimens indicated that tungsten content significantly affects the impact behavior, whereas variations in tungsten particle size have a negligible influence on the Hugoniot pressure. A high tungsten content with small particle size (e.g., 90 wt% with ~200 μm) improves the overall compressive properties of composite materials. Based on the experimental results, a mesoscale finite element model consistent with the tests was developed. The overall error between the numerical simulations and experimental results was less than 5% under various conditions, thereby validating the accuracy of the model. Numerical simulations revealed the coupling mechanism between tungsten particle plastic deformation and matrix flow. The strong rarefaction unloading effect initiated at the composite's free surface caused matrix spallation and jetting. Multiple wave systems were generated at the composite-copper interface, whose interference and coupling ultimately resulted in a nearly uniform macroscopic pressure field.
钨粉/聚四氟乙烯（W/PTFE）复合材料有潜力取代传统金属材料，用作可控动力弹头的外壳。在爆炸载荷作用下，它们会产生高密度且分布相对均匀的金属粉末颗粒，从而增强近距离冲击效果，同时减少附带损伤。为了表征材料在冲击载荷下的响应，进行了平板冲击试验，以研究钨含量（70 wt%、80 wt%和90 wt%）和钨颗粒尺寸（200μm、400μm和600μm）对复合材料冲击行为的影响。使用37毫米单级轻气炮和全光纤激光干涉仪（DISAR）测量靶板的自由表面速度历程，从而确定冲击速度-颗粒速度关系，以建立状态方程。实验数据表明冲击速度与颗粒速度之间存在线性关系，80 wt%和90 wt%的复合材料表现出相似的冲击速度。随着钨质量分数从70 wt%增加到90 wt%，拟合斜率从2.792增加到2.957。随着颗粒尺寸从200μm增加到600μm，斜率从3.204减小到2.756，而 从224.7增加到633.3。不同试样的雨贡纽压力曲线比较表明，钨含量显著影响冲击行为，而钨颗粒尺寸的变化对雨贡纽压力的影响可忽略不计。高钨含量且小颗粒尺寸（例如，90 wt%且约200μm）可改善复合材料的整体压缩性能。基于实验结果，建立了与试验一致的细观尺度有限元模型。在各种条件下，数值模拟与实验结果之间的总体误差小于5%，从而验证了模型的准确性。数值模拟揭示了钨颗粒塑性变形与基体流动之间的耦合机制。在复合材料自由表面引发的强烈稀疏卸载效应导致基体层裂和喷射。在复合材料-铜界面产生了多个波系，它们的干涉和耦合最终导致了近乎均匀的宏观压力场。
