Abstract
Burning characteristics of ammonium nitrate (AN)/ammonium perchlorate (AP) propellants depend on the particle size of AP and fraction of an oxidizer. The burning characteristics of AN/AP propellants were improved using fine AP (FAP) and adding a catalyst. FAP with a mean diameter of 1.7 μm was used, and MnO2 and Fe2O3 were used as catalysts. The burning rate increased as the mass ratio of FAP to the oxidizer content increased. The effect of the catalyst on the increase in the burning rate increased in the order MnO2<Fe2O3 ≤ bicatalyst. The AN/FAP propellants exhibited unstable burning behaviors. The range of the unstable burning behavior was reduced by the addition of the catalyst, and the effect was enhanced in the following order: MnO2<bicatalyst<Fe2O3. The burning characteristics were compared to those of the AN/AP propellant containing another FAP with a mean diameter of 4.1 μm; the difference in the particle size of FAP was only a 2.4 μm. The burning rates of the AN/FAP propellants hardly depend on the particle diameter of FAP. However, the range of the unstable burning behaviors increased with the use of finer AP because of the differences in the burning rates of the FAP-filled region supplemented with Fe2O3.
