A system and method for producing fuel grain for a rocket engine horizontally with an additive manufacturing machine is disclosed. To begin, a fuel grain model is received. The fuel grain model is oriented in a direction of a central core axis and divided into two-dimensional layers with defined footprint areas. In accordance with the fuel grain model, a first layer is printed by applying successive fuel beads in a direction primarily parallel to the central core axis.

A method of making RDX nanoparticles comprises dissolving RDX in acetone; injecting the RDX/acetone through an inner tube of a turbulent mixer to form an inner flow; injecting an anti-solvent through an outer tube of a turbulent mixer to form an outer flow, wherein the inner tube is concentric with the outer tube, wherein turbulent mixing of the inner flow and outer flow precipitates nanoparticle of RDX. The concentration of RDX in acetone may be 0.5-1.0 mg RDX/mL acetone. The anti-solvent is a mixture of hexane and cyclohexanone.

The present invention comprises formulations and method for additive manufacturing comprising: a pot-stable photo-curable polymer; one or more fillers; and one or more additives, wherein the formulation cures into a polymer in six hours or less upon exposure to light. In certain examples, the additive manufacturing is a moldless method of additive manufacturing by preparing a formulation comprising: a pot-stable photo-curable polymer, one or more fillers, and one or more additives, and exposing the formulation to light in an amount that substantially cures the polymer in 6 hours or less.

A discrete gradient charge that has a discrete first hollow cylindrical layer of a solid first fuel, which is about 85% by weight fine aluminum powder having a median diameter of about 3.5 microns. There is a discrete second hollow cylindrical layer of a solid second fuel that is about 80% by weight coarse aluminum powder with a median diameter of about 31.0 microns. The fuels have a cured HTPB binder. A pellet of an explosive positioned within the first hollow cylindrical layer provides ignition. The fuel in the charge reacts with the surrounding air or with a hollow cylindrical oxidizer layer, or a combination thereof.

The present invention comprises formulations and method for additive manufacturing comprising: a pot-stable photo-curable polymer; one or more fillers; and one or more additives, wherein the formulation cures into a polymer in six hours or less upon exposure to light. In certain examples, the additive manufacturing is a moldless method of additive manufacturing by preparing a formulation comprising: a pot-stable photo-curable polymer, one or more fillers, and one or more additives, and exposing the formulation to light in an amount that substantially cures the polymer in 6 hours or less.

Three-dimensional (3D) printed fluoropolymer-based energetic compositions are made using 3D printing methods. The 3D printed fluoropolymer-based energetic compositions comprise a fluoropolymer and a reactive metal or metal oxide. The total weight percentage of the fluoropolymer and the reactive metal or metal oxide is 70-100% of the 3D printed fluoropolymer-based energetic composition, and the weight percentage of the reactive metal or metal oxide is 5-85 wt % of the total weight of the 3D printed fluoropolymer-based energetic material. The 3D printed fluoropolymer-based energetic material has a thickness of at least 200 μm.

The conformable pyrolant includes a fluorocarbon liquid, a fluorocarbon powder, and a micron size powdered aluminum bound together with a binder system that includes polyisobutylene and colloidal silicon dioxide. The conformable pyrolant is capable of achieving temperatures on the order 10,000 F., which will breach an ordnance item and thermally decompose an insensitive explosive fill. The conformable pyrolant also includes tungsten, wherein tungsten and silicon dioxide oxidize into fluorinated compounds, therein extending the burn and gasifying, therein enhancing ebullition and volume in general. The versatile conformable format is capable of being shaped into geometries for inclusion in ordnance items or molded into configurations for disposal of insensitive munitions.

A method of manufacturing and optimizing energetic propellant grains includes generating an optimal surface area to mass fraction burned ratio profile for a predetermined solid structure including propellant grains; using the profile as a target function of a topological optimization process to generate a 3D form of a propellant grain; developing a negative of the 3D form of the propellant grain; mixing and densifying the negative with an energetic material in an uncured form in a mixer to create a structure including the energetic material and embedded negative; and solvating the negative from the structure, wherein the negative comprises a 3D propellant grain. The developing of the negative of the 3D form of the propellant grain may occur using a predetermined material in an additive manufacturing process. The negative may be soluble in the predetermined material, and the energetic material may be insoluble in the predetermined material.

The present invention relates to a manufactured graphene/metal or metalloid core-shell composite and manufacturing method thereof. The method comprising: using a modified graphene oxide as a base, then performing concentration and steam drying followed by organic solvent replacement to obtain a modified graphene oxide organic solvent; using a liquid-phase self-assembly method to coat the modified graphene oxide onto a surface of the metal or metalloid to form a graphene/metal or metalloid coated particle solution, then filtering and drying to obtain the graphene metal/metalloid core-shell composite. The method improves upon a conventional organic and inorganic material coating technique, and reduces an impact of a water-based solvent and high temperature on a highly reactive metal and metalloid, thereby expanding the feasibility of the coating technique and addressing a barrier of applicability of graphene and reactive metal or metalloid in the field of energetic materials.

The present disclosure relates to three-dimensional (3D) printed fluoropolymer-based energetic compositions and 3D printing methods for making the 3D printed fluoropolymer-based energetic compositions.