Studies on High Burning Rate Composite Propellant Formulations using TATB as Pressure Index Suppressant

Abstract: High burning rate propellant compositions are generally used in gas generators to eject missile from canister. Because of high burning rate, pressure index of the composition increases during burning. To reduce the pressure index, a high burning rate composite propellant formulations (~20 mm/s) based on AP/HTPB/Al have been prepared by incorporating TATB and studied in detail for viscosity build-up, thermal and mechanical properties, sensitivity as well as burning rate and pressure index (n). The data indicate that there is a decrease in end of mix viscosity on increasing the percentage of TATB. The same trend was also observed with mechanical properties while significant improvement in overall thermal stability was clearly observed. The sensitivity data indicate that impact and friction values show decreasing trend infer better safe to handle. The burn rate data reveal that on addition of TATB from 0.5 to 2 % decrease in burning rate was not observed while on addition of further TATB up to 5 % and beyond this significant decrease in burning rate was observed. The data on pressure index (n) also reveal that TATB is very effective in reducing the ‘n ’ value up to 2 % and beyond this ‘n’ value increases close to standard composition. The data on ‘n ’ value reveal that it reduces from 0.47 to that of standard composition to 0.36 for the compositions containing TATB up to 2.0 % in the pressure range of 60-90 kg/cm2