# US 2018/0025793 A1 · Cold spray chromium coating for nuclear fuel rods > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0025793 A1 - Document ID: US20180025793A1 - Status: Published application - Kind: A1 - Application number: 15/284,076 - Filed: 2016-10-03 - Published: 2018-01-25 - Earliest claimed: 2016-07-22 - Assignees: Westinghouse Electric Corp.; Wisconsin Alumni Research Foundation - Applicants: Westinghouse Electric Company LLC; Wisconsin Alumni Research Foundation - Inventors: EDWARD J. LAHODA; PENG XU; ZESES KAROUTAS; SUMIT RAY; KUMAR SRIDHARAN; BENJAMIN MAIER; GREG JOHNSON - Web page: https://patentgrep.com/patent/US20180025793A1 ## CPC - G21C 3/07: characterised by their material, e.g. alloys - B32B 15/01: all layers being exclusively metallic {(making layered metal workpieces by pressure cladding B23K20/22; making coatings with a metallic material characterised by its composition C23C30/00)} - C23C 24/08: by application of heat or pressure and heat (C23C24/04 takes precedence) - C23C 24/082: {without intermediate formation of a liquid in the layer} - C23C 24/087: {Coating with metal alloys or metal elements only} - C23C 30/00: Coating with metallic material characterised only by the composition of the metallic material, i.e. not characterised by the coating process (C23C26/00, C23C28/00 take precedence) - G21C 21/02: Manufacture of fuel elements or breeder elements contained in non-active casings - Y02E 30/30: Nuclear fission reactors - G21C: NUCLEAR REACTORS (fusion reactors, hybrid fission-fusion reactors G21B; nuclear explosives G21J) - B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM - C23C: COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL (making metal-coated products by extrusion B21C23/22; covering with metal by connecting pre-existing layers to articles, see the relevant places, e.g. B21D39/00, B23K; metallising of glass C03C; metallising mortars, concrete, artificial stone, ceramics or natural stone C04B41/00; enamelling of, or applying a vitreous layer to, metals C23D; treating metal surfaces or coating of metals by electrolysis or electrophoresis C25D; single-crystal film growth C30B; by metallising textiles D06M11/83; decorating textiles by locally metallising D06Q1/04) - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract A method is provided for coating the substrate of a component, such as a zirconium alloy cladding tube, for use in a water cooled nuclear reactor under normal operating conditions and under high temperature oxidation conditions. The method includes heating a pressurized carrier gas to a temperature between 200° C. and 1200° C., adding chromium or chromium-based alloy particles having an average diameter of 20 microns or less to the heated carrier gas, and spraying the carrier gas and particles onto the substrate at a velocity, preferably from 800 to 4000 ft./sec. (about 243.84 to 1219.20 meters/sec.), to form a chromium and/or chromium-based alloy coating on the substrate to a desired thickness. ## Claims ### Claim 1 A method of coating a substrate of a component for use in a water cooled nuclear reactor, the method comprising: heating a pressurized carrier gas to a temperature between 200° C. and 1200° C.; adding particles to the heated carrier gas, the particles being selected from the group consisting of pure chromium, chromium-based alloys, and combinations thereof, and having an average diameter of 20 microns or less; and spraying the carrier gas and entrained particles onto a substrate at a velocity of 800 to 4000 ft./sec. (about 243.84 to 1219.20 meters/sec.) to form a coating on the substrate. ### Claim 2 (depends on 1) The method recited in claim 1 wherein the substrate is a zirconium alloy. ### Claim 3 (depends on 1) The method recited in claim 1 wherein the carrier gas is selected from the group consisting of nitrogen, hydrogen, argon, carbon dioxide, helium, and combinations thereof. ### Claim 4 (depends on 1) The method recited in claim 1 wherein the particles are pure chromium particles. ### Claim 5 (depends on 1) The method recited in claim 1 wherein the carrier gas and entrained particles are sprayed continuously until the desired coating thickness is reached. ### Claim 6 (depends on 1) The method recited in claim 1 wherein the component is a nuclear fuel rod cladding tube. ### Claim 7 (depends on 1) The method recited in claim 1 wherein the substrate is cylindrical in shape. ### Claim 8 (depends on 1) The method recited in claim 1 wherein the substrate is flat. ### Claim 9 (depends on 1) The method recited in claim 1 wherein the coating thickness is between 5 and 100 microns. ### Claim 10 (depends on 1) The method recited in claim 1 wherein the rate of particles deposition is up to 1000 kg/hour. ### Claim 11 (depends on 1) The method recited in claim 1 further comprising, following formation of the coating, annealing the coating. ### Claim 12 (depends on 1) The method recited in claim 1 further comprising, following formation of the coating, increasing the smoothness of the coating. ### Claim 13 (depends on 1) The method recited in claim 1 wherein the chromium-based alloy particles comprise 80 to 99 atom % of chromium. ### Claim 14 (depends on 13) The method recited in claim 13 wherein the Cr-based alloy further comprises at least one element selected from the group consisting of silicon, yttrium, aluminum, titanium, niobium, zirconium, and transition metal elements, at a combined content of 0.1 to 20 atomic %. ### Claim 15 (depends on 1) The method recited in claim 1 wherein the carrier gas is heated at a pressure up to 5.0 MPa. ### Claim 16 A cladding tube for use in a water cooled nuclear reactor comprising: a cladding tube formed from a zirconium alloy and having a coating uniformly deposited thereon, the coating selected from the group consisting of chromium, a chromium-based alloy, and combinations thereof. ### Claim 17 (depends on 16) The cladding tube recited in claim 16 wherein the coating is up to 300 microns thick. ### Claim 18 (depends on 16) The cladding tube recited in claim 16 wherein the coating is a Cr-based alloy comprising at least one element selected from the group consisting of silicon, yttrium, aluminum, titanium, niobium, zirconium, and transition metal elements, at a combined content of 0.1 to 20 atomic %. ### Claim 19 (depends on 16) The cladding tube recited in claim 16 wherein the coating is a Cr-based alloy comprises 80 to 99 atom % of chromium.