Influence of Solid Particle Size on Burning and Mechanical Properties of AP/Al/HTPB Composites

Abstract

Mechanical and ballistics properties are a measure of the performance of AP/Al/HTPB composites. These properties are influenced by the characteristics of inorganic crystalline oxidizer and aluminum particles. This paper reports the effect of the particle size distribution on mechanical and burning properties of 87% solid loaded composites. Composites were fabricated by mixing the ingredients in the planetary mixer followed by curing at an elevated temperature for several days. Multimodal particle size distribution was used in which coarse to fine ratio was varied proportionally. The burning rate was measured using strand burner at various pressures. Mechanical properties of the composites were investigated by using tensile tester. Results revealed that tensile strength and the burning rate increased while elongation at maximum stress decreased with the increase in the quantity of fines oxidizer. Whereas the variation in the particle size of the aluminum do not have any pronounced effect on the burning as well as mechanical properties of the composite.