Binary Mixture Based on Epoxy for Spectrally Adapted Decoy Flare

Abstract

Pyrotechnic decoy flares are the most widely used passive countermeasures for heat-seeking missiles. The development of (photoconductive) InSb-detectors with cut-off wavelength>6 μm has allowed two-color detectors working in both short (<em>α</em>) (1.8-2.5 μm) and mid-wave (<em>β</em>) (3.5-4.8 μm) bands. Thus, it is possible to determine the sensitivity ratio and to discriminate against fake targets. An attempt was made to change the spectral distribution of MTV (Magnesium-Teflon-Viton) decoy flare compositions by adding another composition to modify spectral emission based on aluminum, hexamine, potassium nitrate and ammonium perchlorate. Aluminum emission at 1.5 µm due to Al₂O₃. Hexamine used as flame expanders due and to provide cooling of the flame to transform radiation from a spot location to a burning zone. In this study, theoretical and experimental comparisons were made between various spectrally adapted flame compositions based on epoxy as a binder and the MTE flare which represented by sample (4). The first composition was Mg/Teflon/Epoxy (MTE) with percentage (60-80)% and the second adapted compositions with percentage (20-40)%. The temperature of the flame and the time of burning were measured using an inframetric radiometer. The radiant emission was determined using a computer program. The results show that sample (1) which contains 20% of the adapted compositions produces high flame temperature (1300 °C) and the highest radiant emittance 6.6 W/cm²/µm.