Effects of Nano-Rod Hematite Iron Oxide on the Properties of a Composite Solid Propellant

Iron oxide as a burning rate catalyst is commonly used in many of solid composite propellants. As the particle size of this component decreased, the final properties of the propellant change. In this research, effects of using 1 percent by weight of nano hematite iron oxide (α-Fe2O3) on the properties of an HTPB/AP/Al formulation is investigated and is is compared with the properties of same propellant containing micronized iron oxide. Nano Fe2O3 has a rod shape with a diameter of 40 nm and a length of about 150 nm. The test performed on the propellant slurry showed that applying nano particles instead of micronized powder increase the viscosity from 4.1 to 6.3 kp. Tensile strength and hardness of cured sample were also increased (22 and 5%, respectively). While strain was reduced (56 to 45%). This replacement enhanced the burning rate of propellant by an average of about 20%. Also, the pressure index (n) changed from 0.3927 to 0.3517.