Quantitative reactive release energy models of Al/Teflon material during high velocity impact

Abstract

Summary The reactive release energy of Al/Teflon projectile impacting on steel plate has a theoretical significance to explain the mechanism of shock‐induced reaction and impact initiation threshold of fluoropolymer‐based reactive materials. During the process of impact‐reaction in quasi‐closed container, the distributions of initial kinetic energy and impact reactive release energy are attributed to the gas enthalpy change, enthalpy change of spray gas, the internal energy absorbed by the container wall and the residual kinetic energy of the unreacted debris. Based on theoretical and experimental analysis, the energies allocated to each part are evaluated quantitatively. The results show that when the impact velocities are 402, 458, and 514 m/s, the reactive release energies of Al/Teflon are 3.276, 4.193, and 4.663 kJ/g, respectively. With the increase of projectile's velocity, the gas energy in the container, the spray gas energy and the internal energy absorbed by the container wall also increase, however the kinetic energy of the unreacted debris changes less. The internal energy absorbed by the container wall accounts for more than 90% of the total energy, and the total gas enthalpy change generated is less than 10%.