锆/聚四氟乙烯活性材料的动态压缩特性

Dynamic Compression Characteristics of Zirconium/polytetrafluoroethylene Reactive Material

采用弹道枪和高温同步分离式霍普金森压杆装置研究了锆/聚四氟乙烯(Zr/PTFE)活性材料在高应变率下的撞击反应特性和动态力学行为。高速摄影结果显示,Zr/PTFE活性材料撞击钢靶时可以发生剧烈的化学反应,放出大量的热。材料的反应持续时间强烈地依赖于撞击速度。在应变率范围6000~10800 s-1内,活性材料的动态压缩应力-应变曲线呈现出典型弹性-塑性强化的变形特征;材料的屈服强度和强度极限均反映出材料有明显的温度软化效应。扫描电镜结果显示,Zr/PTFE活性材料的主要失效机制是金属颗粒和聚四氟乙烯基体的脱粘以及聚四氟乙烯基体的变形。

The impact initiation characteristics and dynamic compressive properties of zirconium/polytetrafluoroethylene(Zr/PTFE)reactive material were studied using ballistic gun and modified split Hopkinson pressure bar(SHPB)with pneumatically synchronous,respectively.The high speed photographic results show that Zr/PTFE reactive material can react violently and release a large amount of heat under impact.The reaction duration is obviously affected by the impact velocity.The dynamic compressive stress-strain curves of reactive material exhibit the typical elastic-plastic hardening characteristics in the strain rate range of 6000-10800 s-1,and the yield strength and ultimate strength reflect obvious thermal softening effect of material.Scanning electron microscopic results indicate that the deformation of PTFE matrix and the separation of metal particles from the matrix are the major mechanisms leading to the failure of Zr/PTFE reactive material.