SHPB加载下PTFE/Al冲击反应的临界条件  

Impact-induced initiation criteria of PTFE/Al by split Hopkinson pressure bar

作　　者：乌布力艾散.麦麦提图尔荪 葛超 田超 董永香[1] Wubuliaisan MAIMAITITUERSUN;GE Chao;TIAN Chao;DONG Yongxiang(State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology,Beijing 100081,China)

机构地区：[1]北京理工大学爆炸科学与技术国家重点实验室,北京100081

出　　处：《爆炸与冲击》2018年第5期957-965,共9页Explosion and Shock Waves

基　　金：国家自然科学基金项目(11202028;11472053)

摘　　要：采用分离式霍普金森压杆(SHPB)加载方法和高速摄影技术,对混合压制烧结法制备的铝颗粒增强聚四氟乙烯复合材料(polytetrafluoroethylene/Al,PTFE/Al)的冲击反应临界条件进行研究。实验中采用钢杆、铝杆和不同尺寸的试样,进行不同加载条件下的测试,实验结果表明:PTFE/Al复合材料的冲击反应过程主要可分为变形、碎裂、反应阶段,其冲击反应临界同时关联于应力和应变率。并基于实验获得了PTFE/Al复合材料的冲击反应临界渐进线应力和应变率,通过对实验数据的归纳和分析,初步提出实验条件下关联应力和应变率的PTFE/Al临界反应关系式,获得冲击反应阈值预测曲线。Impact-induced initiation criteria of Al particles reinforced PTFE(PTFE/Al)prepared by compression/sintering were studied by split Hopkinson pressure bar(SHPB)and high speed photography in this work.SHPB systems comprising of either steel or aluminum bars were applied to test PTFE/Al samples of different dimensions,in order to study the effect of the impact stress and the loading strain rate on the impact-induced initiation behaviors of PTFE/Al.It shows that the impact-induced initiation process of PTFE/Al mainly includes the deformation,fragmentation and reaction,which is simultaneously related to the impact stress and the loading strain rate.Based on the experimental results,the criteria of impact stress and loading strain rate for the impact-induced initiation of PTFE/Al have been obtained.Moreover,an analytical expression of impact-induced initiation criteria including impact stress and loading strain rate was established and a theoretical curve was predicted for the impact-induced initiation events of PTFE/Al under SHPB tests.

关 键 词：PTFE/Al 分离式霍普金森压杆 冲击反应 临界条件 

分 类 号：O383.3[理学—流体力学] TJ04[理学—力学]