活性反应材料力学性能和点火特性研究

发布时间：2018-04-29 09:59

本文选题：聚四氟乙烯/铝/钨 + 反应材料　；参考：《国防科学技术大学》2015年硕士论文

【摘要】：反应材料是一种在高聚物中填充金属、合金等非炸药成分的含能材料,在高速撞击作用下会快速发生反应,释放能量。为了研究未发生损伤和发生损伤的反应材料在不同撞击作用下的力学性能和点火特性,本文分别使用了实验研究、理论分析和仿真计算的方法,最终得到了聚四氟乙烯/铝/钨材料在撞击过程中的宏观力学特性和点火特性变化的规律。针对反应材料的力学性能和点火特性试验研究,首先使用分离式霍普金森杆(SHPB)对反应材料进行中低应变率加载,获得了SHPB加载下材料的力学特性,拟合了材料的Johnson-Cook本构模型,并通过LS-DYNA仿真计算,验证了模型参数的合理性。其次,分别使用SHPB进行高应变率加载和落锤直接撞击以及压剪加载,得到材料发生反应的临界应力和单位质量材料发生点火反应的输入能量。最后,为了研究损伤对材料的力学性能和点火特性影响,使用静态试验机压缩材料产生预变形,分别使用SHPB和落锤实验进行研究,对比损伤前后材料的力学性能和点火特性,结果表明损伤对材料的力学性能和点火特性具有很大的影响。针对反应材料的反应机理,通过分析反应材料的化学和热学性能,初步得到材料发生反应的可能过程;并引入材料的热塑性模型,使用Fortran编写程序计算加载过程中材料的宏观温度变化,对比实验结果,验证了模型的合理性,初步得到了由于材料的力学性能变化而引起温度变化的规律特性。
[Abstract]:Reactive material is a kind of energetic material which is filled with metal, alloy and other non-explosive components in high polymer. It can react rapidly and release energy under the action of high velocity impact. In order to study the mechanical properties and ignition characteristics of non-damaged and damaged reactive materials under different impacts, the methods of experimental study, theoretical analysis and simulation calculation are used in this paper. Finally, the macroscopic mechanical properties and ignition characteristics of PTFE / Al / W materials during impact are obtained. Based on the experimental study of mechanical properties and igniting characteristics of reactive materials, the split Hopkinson rod SHPBwas first used to load the reactive materials at low strain rate. The mechanical properties of the materials under SHPB loading were obtained, and the Johnson-Cook constitutive model of the materials was fitted. The rationality of the model parameters is verified by LS-DYNA simulation. Secondly, the critical stress of material reaction and the input energy of ignition reaction per unit mass are obtained by using SHPB to carry out high strain rate loading, direct impact of drop hammer and compression shear loading respectively. Finally, in order to study the effect of damage on the mechanical properties and ignition characteristics of materials, predeformation was produced by using static testing machine. SHPB and drop weight experiments were used to compare the mechanical properties and ignition characteristics of the materials before and after the damage. The results show that the damage has a great influence on the mechanical properties and ignition properties of the materials. According to the reaction mechanism of the reaction material, the possible process of the material reaction is preliminarily obtained by analyzing the chemical and thermal properties of the reaction material, and the thermoplastic model of the material is introduced. The macroscopic temperature change of the material during loading is calculated by using Fortran program. The rationality of the model is verified by comparing the experimental results. The regular characteristics of temperature change caused by the change of mechanical properties of the material are preliminarily obtained.
【学位授予单位】：国防科学技术大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB301

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