Mechanical and Reaction Properties of PTFE/Al/MnO<sub>2</sub> Reactive Materials at Different Strain Rates

Abstract

The mechanical responses of the PTFE/Al/MnO 2 reactive material in the strain rate range of 10-3~4 ×10 3 s-1 were studied by a universal testing machine and split Hopkinson pressure bar (SHPB) system, and the microstructure of PTFE/Al/MnO 2 specimen was observed by Scanning Electron Microscope (SEM). Meanwhile, a standard drop-weight apparatus was used to reveal the reaction properties and impact sensitivity of the PTFE/Al/MnO 2 reactive material. The results demonstrate that under quasi-static compression conditions, the yield strength and compressive strength of PTFE/Al/MnO 2 specimens have obvious strain rate effects, while the elastic modulus and failure strain are insensitive to strain rate and remain almost unchanged. Under dynamic load conditions, the compressive strength of the PTFE/Al/MnO 2 specimen has a linear relationship with the logarithm of the strain rate, while the critical strain and the logarithm of the strain rate show a parabolic relationship. The established constitutive equation can describe the mechanical behavior of PTFE/Al/MnO 2 material at high strain rate well, which can provide a reference to the practical applications of the material. PAM specimens can react violently under the impact of a drop hammer, with intense light and a huge explosion sound. And the characteristic drop height of the PAM specimen was calculated as 58.13cm.

Energy Release Characteristics and Reaction Mechanism of PTFE/Al/Bi2O3 Reactive Materials under Drop-Hammer Test

“…Since PTFE/Al and thermite have the same reaction component metal, i.e., Al, the combination of PTFE/Al reactive materials with thermite is a new approach to improving the energy release characteristics of PTFE/Al-based reactive materials [ 5 , 6 , 7 ]. Therefore, the formulations and preparation processes for obtaining ternary reactive materials that can initiate thermite reactions and have unique impact reaction properties have become a hot topic [ 8 , 9 , 10 , 11 ].…”