Dynamic constitutive model and ignition behavior of enhanced Al/PTFE

Al/PTFE reactive material is a kind of energetic material with direct damage ability. Numerical simulation is one of the most effective ways to investigate the internal damage and impact induced ignition mechanism. However, there is no suitable constitutive equation to describe the mechanical behavior of the reactive material under the impact load, therefore an appropriate constitutive model of the reactive material is of great significance. In order to obtain an appropriate constitutive model to describe the mechanical properties and impact induced ignition behavior of the material, the enhanced Al/PTFE reactive material was prepared by cold pressing and rapid cooling process. The dynamic mechanical properties of the enhanced Al/PTFE specimens under different strain rates were tested by using the SHPB/SHTB testing systems. And the parameters of the Zhu-Wang-Tang (ZWT) constitutive model were calibrated. Based on ZWT constitutive model, numerical simulation of Flattened Bra-zilian splitting was carried out. And dynamic compressive/tensile mechanical properties of enhanced Al/PTFE reactive material were obtained by combining theoretical derivation and numerical simulation of ABAQUS/ Explicit. The effectiveness of this model is verified by comparing experimental and numerical simulation results. Futhermore, combined ZWT constitutive model with Equation of State (EOS) of ignition and growth, ANSYS/ AUTODYN was used to simulate the process that Al/PTFE reactive material impacted the target. The destruction and ignition behavior of the projectile under the interaction of stress wave were explained.