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.

A combustible element includes regions of fuel material interspersed with regions of oxidizer material. The element may be made by additive manufacturing processes, such as three-dimensional printing, with the fuel material regions and the oxidizer material regions placed in appropriate locations in layer of the combustible element. For example, different extruders may be used to extrude and deposit portions of a fuel filament and an oxidizer filament at different locations in each layer of the combustible element. The combustible element may define a combustion chamber within the element, where combustion occurs when the combustible element is ignited. The fuel material and the oxidizer material may be selected, and their relative amounts may be controlled, such that desired relative amounts of fuel and oxidizer are present for combustion with desired characteristics, such as combustion rate.

A combustible element includes regions of fuel material interspersed with regions of oxidizer material. The element may be made by additive manufacturing processes, such as three-dimensional printing, with the fuel material regions and the oxidizer material regions placed in appropriate locations in layer of the combustible element. For example, different extruders may be used to extrude and deposit portions of a fuel filament and an oxidizer filament at different locations in each layer of the combustible element. The combustible element may define a combustion chamber within the element, where combustion occurs when the combustible element is ignited. The fuel material and the oxidizer material may be selected, and their relative amounts may be controlled, such that desired relative amounts of fuel and oxidizer are present for combustion with desired characteristics, such as combustion rate.

A reactive composite foil, including metallic fuel particles, oxidizer particles, and a diluent, which, when ignited, produces a self-propagating thermite reaction to produce a molten metal.

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.

A method for obtaining the explosive charge in dry granular form as well as a device suitable for implementing the method. The method includes: filtering the suspension, by passing same through a static filter in order to obtain a cake containing the granular explosive charge agglomerated by residual liquid; dewatering the cake by subjecting the cake to pressurized gas; splitting the dewatered cake and obtaining a fluidized bed of the desired explosive charge by exposing the dewatered cake to at least one stream of gas; at least one stream of gas being injected, under the dewatered cake to impinge said dewatered cake, according to two consecutive modes and the gas having a humidity height below that of the dewatered cake and a dew point temperature higher than the injection temperature thereof; and stopping at least one stream of gas and recovering the explosive charge in dry, granular form.

A method of additively manufacturing propellant elements, such as for rocket motors, includes partially curing a propellant mixture before extruding or otherwise dispensing the material, such that the extruded propellant material is deposited on the element in a partially-cured state. The curing process for the partially-cured extruded material may be completed shortly after the material is put into place, for example by the material being heated at or above its cure temperature, such that it finishes curing before it fully cools. The propellant material may be prepared by first mixing together, a fuel, an oxidizer, and a binder, such as in an acoustic mixer. After that mixing a curative may be added to the mixture. The propellant mixture may then be directed to an extruder (or other dispenser), in which the mixture is heated to or above a cure temperature prior to the deposition, and then deposited.

An additively manufactured solid fuel grain for a hybrid rocket engine having a cylindrical shape, defining a center combustion port and comprising a stack of fused layers of polymeric material suitable for hybrid rocket fuel. Each layer is formed as a plurality of fused abutting concentric beads of solidified material arrayed around the center port. An oxidizer is introduced into the solid fuel grain through the center port, with combustion occurring along the exposed surface area of the solid fuel grain center port wall. Each concentric bead possesses a surface pattern that increases the combustion surface area and when stacked forms a rifling pattern of undulations that induces oxidizer-fuel gas axial flow to improve combustion efficiency. The port wall surface pattern persists during the rocket engine's operation as the fuel phase changes from solid to gas and is ablated.

A method for obtaining the explosive charge in dry granular form as well as a device suitable for implementing the method. The method includes: filtering the suspension, by passing same through a static filter in order to obtain a cake containing the granular explosive charge agglomerated by residual liquid; dewatering the cake by subjecting the cake to pressurized gas; splitting the dewatered cake and obtaining a fluidized bed of the desired explosive charge by exposing the dewatered cake to at least one stream of gas; at least one stream of gas being injected, under the dewatered cake to impinge said dewatered cake, according to two consecutive modes and the gas having a humidity height below that of the dewatered cake and a dew point temperature higher than the injection temperature thereof; and stopping at least one stream of gas and recovering the explosive charge in dry, granular form.

The invention is a multi-layer thermite block, encased in an exterior protective shield with one face exposed. The exposed face is carved out to accommodate a target device such that the block encompasses the target device when placed atop the device. When receiving a data-destruction signal, the block is ignited producing a short-duration blast of heat sufficient to severely damage or destroy all physical data-storing facilities of the target device.