Preparation Process And Dynamic Mechanical Property Of Metal/PTFE Reactive Materials

The metal / polymer reactive material is a new type of multifunctional structure reactive material, which is generally composed of polytetrafluoroethylene(PTFE) serving as matrix, active metal composite serving as filler composition. Compared with the traditional reactive materials, PTFE based reactive material is insensitive in general and has certain properties at high temperature. It will not react with each other between the components and react with the air. But under the effect of external physical impact, the material can quickly react and energy release can greatly improve the penetration armor piercing effect and result in significant aftereffect such as combustion, detonation, implosion, which improve the damage effect on the target. In this paper, the preparation process, mechanical properties and reaction characteristics of PTFE based reaction materials will be studied.First, the preparation process of the material was analyzed. The preparation process of the material consist of modification, mixing, drying, molding and sintering. Combined with the quasi static compression experiments, analysis of the effects of molding pressure, particle size, filler content, sintering temperature and sintering time. Then the best preparation technology is summarized.With the split Hopkinson pressure bar(SHPB) test method, research the dynamic characteristics of Zr/PTFE reactive material and Al/W/PTFE reactive material. Experiments show that when the strain rate increases, the compressive strength of the material increases significantly, while the elastic modulus and the hardening modulus changes little. Based on the Johnson cook elasto plastic constitutive model we found Zr/PTFE reaction material constitutive equation, and establish the constitutive equation for Al/W/PTFE reactive material based on foam material constitutive model. At the same time, studied the reactive characteristics of Al/W/PTFE reaction materials. Experiments show that with the increasing of content of W, the material impact response thresholds were elevated, and the intensity weakens.Use LS-DYNA to establish a three-dimensional finite element model of the split Hopkinson pressure bar(SHPB), and the material model was defined as the J-C model of Zr/PTFE reactive material. The waveform of simulation correspond to the waveform of experiment. It is proved that the constitutive equation is correct.