PBXs (Plastic Bonded Explosives) are highly filled particulate composite materials with high filler content. The PBX developers make a constant effort to improve the PBX energetic performance by increasing the filler content in the matrix, while maintaining or decreasing the product sensitivity. Increasing the filler content is problematic because the viscosity rises to high values, which makes the composition inapplicable for further processing. In addition, high filler content imposes new production difficulties, such as longer mixing time and homogeneity problems during the composition processing (casting or injection molding). This paper describes a novel technology to round explosive particles. The rounded powder has better packing density and higher flow rate, thus enabling higher solid loading. SEM pictures reveal that particles with an originally rectangular or prism-like shape become "potato"-shaped or rounded. Tests show that the packing density of the rounded HMX powder is higher than that of the raw HMX powder (81%TMD vs. 72% TMD, respectively). Flow rate of the composition with rounded powder is higher than that of the composition with raw non-rounded HMX (529g/min vs. 18g/min, respectively). Mechanical properties are improved as well. This paper presents the benefits of using Particle Rounded Technology (PRT) for highly-energetic PBX compositions. This technology is complementary to other manufacturing technologies (i.e. casting and injection molding). It enables casting of high solid loaded compositions, which could not be cast properly otherwise. In addition, high solid loaded compositions can be processed by injection molding techniques, making it possible to manufacture complicated energetic charge shapes or shapes with large L/D.
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