Mechanism of burning rate enhancement of composite solid propellants by ferric oxide

This paper reports a series of experimental studies performed on sandwich propellants, wherein a matrix lamina of particulate oxidizer and polymeric binder is sandwiched between two ammonium perchlorate (AP) Laminae. The catalyst (ferric oxide) is incorporated in the matrix lamina. The variables are pressure (0.345-6.9 MPa), matrix lamina thickness, catalyst concentration, matrix mixture ratio, types of oxidizer and binder, and the dispersion ability of the catalyst. The combined results indicate that, under the conditions tested, near-surface reactions associated with the particulate AP/binder contact lines on the burning surface assume significance in the presence of the catalyst. These reactions are further augmented by the presence of the leading-edge portion of the diffusion name above the interface of the matrix and AP laminae.