# US 2016/0355447 A1 · Additive manufactured combustible element with fuel and oxidizer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2016/0355447 A1 - Document ID: US20160355447A1 - Status: Published application - Kind: A1 - Application number: 14/729,429 - Filed: 2015-06-03 - Published: 2016-12-08 - Earliest claimed: 2015-06-03 - Assignees: Raytheon Company - Applicants: Raytheon Company - Inventors: Jeremy C. Danforth; Mark T. Langhenry; Matt H. Summers; Teresa Perdue - Web page: https://patentgrep.com/patent/US20160355447A1 ## CPC - C06B 45/10: the organic component containing a resin - C06B 21/0033: {Shaping the mixture} - F02K 9/12: made of two or more portions burning at different rates {or having different characteristics} - B33Y 10/00: Processes of additive manufacturing - B33Y 80/00: Products made by additive manufacturing - F05D 2230/31: Layer deposition - C06B: EXPLOSIVES OR THERMIC COMPOSITIONS (blasting F42D); MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES (compounds in general C01, C07 or C08; {demolition agents based on cementitious or like materials C04B41/0009}) - F02K: JET-PROPULSION PLANTS (features of jet-propulsion plants common to gas-turbine plants, air intakes or fuel supply control of air-breathing jet-propulsion plants F02C7/00, F02C9/00) - B33Y: ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS ## Abstract 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. ## Claims ### Claim 1 A combustible element comprises: fuel; and oxidizer; wherein the fuel and the oxidizer are interspersed in discrete separate regions within a single solid element; and wherein the combustible element defines a combustion chamber therewithin where combustion of the fuel and the oxidizer occurs upon ignition of the fuel and the oxidizer. ### Claim 2 (depends on 1) The combustible element of claim 1, wherein the regions include: fuel regions that contain the fuel; and oxidizer regions that contain the oxidizer; and wherein the oxidizer regions also contain a continuous material that acts as a binder. ### Claim 3 (depends on 1) The combustible element of claim 1, wherein the separate regions make up a matrix of regularly-ordered fuel regions and oxidizer regions, with alternating fuel regions and oxidizer regions. ### Claim 4 (depends on 1) The combustible element of claim 1, wherein the element is produced by an additive manufacturing process. ### Claim 5 (depends on 1) The combustible element of claim 1, wherein the fuel includes a first thermoplastic continuous material, with a metal additive. ### Claim 6 (depends on 1) The combustible element of claim 1, wherein the oxidizer includes a second thermoplastic continuous material, with an oxidizer additive. ### Claim 7 (depends on 6) The combustible element of claim 6, wherein the oxidizer additive includes beads of oxidizer material within the second thermoplastic continuous material. ### Claim 8 (depends on 6) The combustible element of claim 6, wherein the oxidizer additive includes droplets of oxidizer material within the second thermoplastic continuous material. ### Claim 9 (depends on 1) The combustible element of claim 1, wherein the fuel-to-oxidizer ratio varies within the solid element, thereby producing one or more of variations in burn rate, or variation of combustion temperature. ### Claim 10 A method of producing a combustible element, the method comprising: successively depositing multiple layers of the element in an additive manufacturing process; wherein the depositing each of the layers includes depositing a matrix of discrete fuel regions that include a fuel material, and discrete oxidizer regions that include an oxidizer material, for that layer. ### Claim 11 (depends on 10) The method of claim 10, wherein the depositing includes selectively depositing fuel material and oxidizer material from heads that are movable relative to the combustible element. ### Claim 12 (depends on 11) The method of claim 11, wherein the heads include heads for extruding the fuel material and the oxidizer material. ### Claim 13 (depends on 12) The method of claim 12, wherein the fuel material and the oxidizer material extruded by the heads is heated material. ### Claim 14 (depends on 12) The method of claim 12, wherein the fuel material and the oxidizer material both include thermoplastic continuous material, used as an extrudable base for the materials. ### Claim 15 (depends on 14) The method of claim 14, wherein the fuel material includes a fuel additive; and wherein the oxidizer material includes an oxidizer additive. ### Claim 16 (depends on 10) The method of claim 10, wherein the method is part of production of a larger structure that the combustible element is a portion of, with portions of the larger structure that are adjacent to the combustible element are also made by an additive manufacturing process. ### Claim 17 (depends on 10) The method of claim 10, wherein the depositing includes depositing different relative amounts of the fuel and the oxidizer in different of the layers. ### Claim 18 (depends on 17) The method of claim 17, wherein the depositing different relative amounts includes varying the ratio of the fuel regions to the oxidizer regions. ### Claim 19 (depends on 17) The method of claim 17, wherein the depositing different relative amounts includes varying size of the fuel regions and/or the oxidizer regions. ### Claim 20 (depends on 10) The method of claim 10, wherein the depositing the layers includes leaving one or more cavities within the combustible element, wherein the one or more cavities are free of deposited material.