Sensitivity of solid rocket propellants for card gap test

Card gap test, which is standardized in Japan Explosives Society, was modif ied in order to apply it to solid rocket propellants and carried out to eva luate sensitivities against shock stimuli. Solid propellants tested here we re mainly azide polymer composite propellants, which contained ammonium nit rate (AN) as a main oxidizer. Double base propellant, composed nitroglyceri n and nitrocellulose (NC), and ammonium perchlorate (AP)-based composite pr opellants were also evaluated in order to compare with the azide polymer pr opellants. It is found that the sensitivity was dominated by the oxidizer c haracteristics. AP-and AN-based propellant had less sensitivity and HMX-bas ed propellant showed higher sensitivity, and the adding of NC and TMETN wer e contributed to worse sensitive for the card gap rest. Good relationship w as obtained between the card gap sensitivity and the oxygen balance of prop ellants tested here.