基于气炮实验的PTFE/Al复合材料冲击反应阈值

Impact-induced initiation thresholds of polytetrafluoroethylene/Al composite by gas gun

基于16 mm口径气炮撞击实验,对铝颗粒增强的聚四氟乙烯(polytetrafluoroethylene)/Al(PTFE/Al)冲击反应复合材料的冲击反应阈值开展了研究。为研究不同撞击加载条件下应变率和碰撞应力对PTFE/Al冲击诱发反应的影响,实验中采用铝、钢和低密度聚乙烯(low density polyethylene,LDPE)这3种不同材料的靶板及不同长度的试样,进行不同加载条件下的测试分析。实验结果显示,PTFE/Al材料的冲击诱发同时受到碰撞压力和加载应变率的影响。同时,通过对试样撞靶过程进行数值模拟,并与实验和理论结果进行对比。基于实验数据,拟合出PTFE/Al材料冲击反应的的预测曲线。

Impact experiments by a gas gun were conducted to investigate the impact-induced initiation thresholds of a PTFE( polytetrafluoroethylene)/Al composite using targets of steel,aluminum and low-density polyethylene( LDPE) materials and sample rods of four different lengths. By subjecting the samples under different loading conditions,it is shown that the impact-induced initiation of PTFE/Al is determined by both the impact pressure and the loading strain rate. The impact pressure and the strain rate thresholds for initiation were arrested by the experiments and the impacting process of the samples was modeled to compare the experimental and theoretical data. Based on all the experimental results,a theoretical curve was proposed to predict the impactinduced initiation of PTFE/Al under normal impact. The method proposed in this research can also be used in the study of other energetic materials.