# How to Make Meltdown-Proof Nuclear Fuel Pellets > This patent describes a method for making a new type of nuclear fuel called Dispersion Ceramic Micro-Encapsulated (DCM) fuel, which uses tiny, specially coated uranium particles embedded in a super-strong silicon carbide material to prevent meltdowns in nuclear reactors. - **Patent:** US 10475543 - **Original title:** Dispersion ceramic micro-encapsulated (DCM) nuclear fuel and related methods - **Owner:** Ultra Safe Nuclear - **Granted:** 2019 - **Status:** Active - **Times cited:** 12 - **Field:** nuclear_energy, materials ## What it does The patent outlines a method (Claim 1) for manufacturing Dispersion Ceramic Micro-Encapsulated (DCM) nuclear fuel. This process involves creating at least two different sizes of 'tristructural-isotropic (TRISO) fuel particles.' Each TRISO particle contains a fuel kernel surrounded by four protective layers: a porous carbon buffer, an inner pyrolytic carbon layer, a ceramic layer, and an outer pyrolytic carbon layer. These TRISO particles are then mixed with a silicon carbide powder and sintered (heated and pressed) using a specific 'nano infiltration transient eutectic phase' to embed them within a dense silicon carbide matrix. This forms a solid fuel compact, or pellet, designed for enhanced safety. For example, Claim 6 details forming the fuel kernel by dissolving material in nitric acid, creating droplets, gelling, calcining, and then coating them in a chemical vapor deposition furnace (Claim 7). ## What it does NOT cover - Does not cover nuclear fuel that uses only a single size of TRISO fuel particles, as Claim 1 specifies "two or more different sizes." - Does not cover fuel compacts where TRISO particles are not dispersed and embedded inside a silicon carbide matrix, as required by Claim 1. - Does not cover manufacturing methods that do not utilize a "nano infiltration transient eutectic phase" for sintering, as specified in Claim 1. - Does not cover TRISO fuel particles that lack any of the four specified layers: porous carbon buffer, inner pyrolytic carbon, ceramic, and outer pyrolytic carbon (Claim 1). - Does not cover fuel compacts formed without pressing in a mold at a predetermined sintering pressure and temperature (Claim 1). ## The clever bit The innovation lies in combining multiple, carefully sized TRISO fuel particles within a highly dense silicon carbide matrix, using a specialized sintering process. This creates a fuel pellet with exceptional structural integrity and multiple layers of containment, making it uniquely resistant to extreme conditions and preventing the release of radioactive materials even if the reactor core overheats. ## Real-world examples 1. Ultra Safe Nuclear Corporation's Fully Ceramic Micro-encapsulated (FCM) fuel 2. Advanced accident-tolerant nuclear fuels (ATF) for light water reactors 3. Next-generation nuclear reactor fuel designs ## Why it matters This patent is significant because it describes a method for creating "meltdown-proof, accident-tolerant fuel" for existing light water reactors (LWRs). By replacing traditional uranium dioxide fuel with DCM fuel, the risk of radioactive material release during a severe accident is substantially reduced due to the multiple robust barriers around the fuel. This technology could enhance the safety of current nuclear power plants and potentially support the development of advanced reactor designs, addressing critical concerns about nuclear safety. ## Frequently asked questions ### What does How to Make Meltdown-Proof Nuclear Fuel Pellets cover? This patent describes a method for making a new type of nuclear fuel called Dispersion Ceramic Micro-Encapsulated (DCM) fuel, which uses tiny, specially coated uranium particles embedded in a super-strong silicon carbide material to prevent meltdowns in nuclear reactors. ### Who owns patent US 10475543? Ultra Safe Nuclear owns this patent, granted in 2019. ### When does this patent expire? This patent is expected to expire on January 31, 2037, when the invention enters the public domain. ### What is patent US 10475543 cited by? This patent has been cited by 12 later patents that build on its ideas. ### What problem does this patent solve? This patent is significant because it describes a method for creating "meltdown-proof, accident-tolerant fuel" for existing light water reactors (LWRs). By replacing traditional uranium dioxide fuel with DCM fuel, the risk of radioactive material release during a severe accident is substantially reduced due to the multiple robust barriers around the fuel. This technology could enhance the safety of current nuclear power plants and potentially support the development of advanced reactor designs, addressing critical concerns about nuclear safety. ### What does this patent NOT cover? Does not cover nuclear fuel that uses only a single size of TRISO fuel particles, as Claim 1 specifies "two or more different sizes." **Full plain-English explainer:** https://patentbrief.org/patent/us/10475543/dispersion-ceramic-micro-encapsulated-dcm-nuclear-fuel-and-related-methods **Original patent:** https://patents.google.com/patent/US10475543 --- _Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._ ## Related patents Semantically similar inventions in the PatentBrief corpus: - [How a Molten Metal Buffer Improves Heat Transfer in Nuclear Reactors](https://patentbrief.org/patent/us/11942229/molten-metal-fuel-buffer-in-fission-reactor-and-method-of-manufacture) — This patent describes a nuclear fission reactor design that uses a liquid molten metal to fill gaps between the nuclear fuel and its protective casing, improving heat transfer and reactor safety. - [How Nuclear Power Plants Reuse Fuel Between Multiple Reactors](https://patentbrief.org/patent/us/10818403/inter-module-fuel-shuffling) — This patent describes a method for nuclear power plants with several reactors to efficiently reuse partially used fuel by moving it between different reactor cores across multiple operating cycles. - [Using Gas Pressure to Safely Control Liquid Fuel Nuclear Reactors](https://patentbrief.org/patent/us/12073952/fail-safe-reactivity-compensation-method-for-a-nuclear-reactor) — This patent describes a method to control a nuclear reaction in liquid-fueled reactors by using gas pressure to adjust the amount of fuel solution in special pipes, ensuring the reactor always returns to a safe state if something goes wrong. - [Making Special Materials Inside Commercial Nuclear Power Plants](https://patentbrief.org/patent/us/9239385/method-of-producing-isotopes-in-power-nuclear-reactors) — This patent describes a method for using the neutron radiation inside large commercial nuclear power reactors, specifically in their existing instrumentation tubes, to create useful isotopes like those used in medicine or industry. - [TerraPower's Molten Salt Reactor with Internal Heat Exchangers](https://patentbrief.org/patent/us/11728052/fast-spectrum-molten-chloride-test-reactors) — This patent describes a unique molten salt nuclear reactor design by TerraPower, featuring an open-topped vessel and integrated heat exchangers for efficient internal cooling and fuel circulation.