Patent application number | Description | Published |
20100108204 | ZIRCONIUM ALLOY COMPOSITION FOR NUCLEAR FUEL CLADDING TUBE FORMING PROTECTIVE OXIDE FILM, ZIRCONIUM ALLOY NUCLEAR FUEL CLADDING TUBE MANUFACTURED USING THE COMPOSITION, AND METHOD OF MANUFACTURING THE ZIRCONIUM ALLOY NUCLEAR FUEL CLADDING TUBE - Disclosed herein is a zirconium alloy composition for nuclear fuel cladding tubes, comprising: 1.6˜2.0 wt % of Nb; 0.05˜0.14 wt % of Sn; 0.02˜0.2 wt % of one or more elements selected from the group consisting of Fe, Cr and Cu; 0.09˜0.15 wt % of O; 0.008˜0.012 wt % of Si; and a balance of Zr, a nuclear fuel cladding tube comprising the zirconium alloy composition, and a method of manufacturing the nuclear fuel cladding tube. Since the nuclear fuel cladding tube made of the zirconium alloy composition can maintain excellent corrosion resistance by forming a protective oxide film thereon under the conditions of high-temperature and high-pressure cooling water and water vapor, it can be usefully used as a nuclear fuel cladding tube for light water reactors or heavy water reactors, thus improving the economical efficiency and safety of the use of nuclear fuel. | 05-06-2010 |
20100322370 | PROCESS OF MANUFACTURING ZIRCONIUM ALLOY FOR FUEL GUIDE TUBE AND MEASURING TUBE HAVING HIGH STRENGTH AND EXCELLENT CORROSION RESISTANCE - A process of manufacturing zirconium alloy. The process may be used to make a nuclear fuel guide tube and/or a measuring tube which are main components of a nuclear fuel assembly structure. While a nuclear fuel guide tube and a measuring tube are manufactured by performing three-step cold working, and intermediate and final thermal annealing from a semi-finished TREX shell in the conventional method, the present invention relates to zirconium alloy undergoing two-step cold working, and intermediate and final thermal annealing from a TREX shell, resulting in enhanced strength and corrosion resistance. The present invention may be applied to a nuclear fuel guide tube and a measuring tube used for a nuclear fuel assembly in a light water nuclear reactor because, by the shortened process, high percentage reduction in thickness between processes and an decrease in thermal annealing time may sustain high strength and excellent corrosion resistance, and achieve economy of manufacture by reducing the number of processes. | 12-23-2010 |
20120145287 | ZIRCONIUM ALLOY COMPOSITIONS HAVING EXCELLENT CORROSION RESISTANCE BY THE CONTROL OF VARIOUS METAL-OXIDE AND PRECIPITATE AND PREPARATION METHOD THEREOF - Disclosed herein are a zirconium alloy composition, which exhibits excellent corrosion resistance by varying the kinds of metal oxides and controlling the size of precipitates of the composition, including: 1.05˜1.45 wt % of Nb; one or more selected from the group consisting of 0.1˜0.7 wt % of Fe and 0.05˜0.6 wt % of Cr; and residual Zr, and a method of preparing the same. The zirconium alloy composition exhibits excellent corrosion resistance by controlling the kinds and amounts of the elements included in the zirconium alloy composition and the heat-treatment temperature and thus varying the kinds of metal oxides formed during an oxidation process and controlling the size of precipitates of the zirconium alloy, so that it can be usefully used as a raw material for nuclear fuel cladding tubes, spacer grids, nuclear reactor internals and the like of a light-water reactor or a heavy-water reactor in a nuclear power plant. | 06-14-2012 |
20130220493 | ZIRCONIUM ALLOYS FOR A NUCLEAR FUEL CLADDING HAVING A SUPERIOR OXIDATION RESISTANCE IN A REACTOR ACCIDENT CONDITION, ZIRCONIUM ALLOY NUCLEAR FUEL CLADDINGS PREPARED BY USING THEREOF AND METHODS OF PREPARING THE SAME - Disclosed are a zirconium alloy for a nuclear fuel cladding having a good oxidation resistance in reactor accident conditions, a zirconium alloy nuclear fuel cladding prepared by using thereof and a method of preparing the same. The zirconium alloy includes 1.0 to 1.2 wt % of niobium (Nb); at least one element selected from tin (Sn), iron (Fe) and chromium (Cr); 0.02 to 0.1 wt % of copper (Cu); 0.1 to 0.15 wt % of oxygen (0); 0.008 to 0.012 wt % of silicon (Si) and a remaining amount of zirconium (Zr). The amount of Sn is 0.1 to 0.3 wt %, the amount of Fe is 0.3 to 0.8 wt %, and the amount of Cr is 0.1 to 0.3 wt %. A good oxidation resistance of the nuclear fuel cladding may be confirmed under accident conditions as well as normal operating conditions of a reactor, thereby improving economic efficiency and safety. | 08-29-2013 |
20130220494 | ZIRCONIUM ALLOYS FOR A NUCLEAR FUEL CLADDING HAVING A SUPERIOR CORROSION RESISTANCE BY REDUCING AN AMOUNT OF ALLOYING ELEMENTS AND METHODS OF PREPARING A ZIRCONIUM ALLOY NUCLEAR FUEL CALDDING USING THEREOF - Disclosed are a zirconium alloy for a nuclear fuel cladding having a good corrosion resistance by reducing an amount of alloying elements and a method of preparing a zirconium alloy nuclear fuel cladding using thereof. The zirconium alloy includes 0.2 to 0.5 wt % of niobium (Nb); 0.2 to 0.6 wt % of iron (Fe); 0.3 to 0.5 wt % of chromium (Cr); 0.1 to 0.15 wt % of oxygen (O); 0.008 to 0.012 wt % of silicon (Si) and a remaining amount of zirconium (Zr). The total amount of the niobium, the iron and the chromium is 1.1 to 1.2 wt %. A good oxidation resistance of the nuclear fuel cladding may be confirmed under accident conditions as well as normal operating conditions of a reactor, thereby improving economic feasibility and safety. | 08-29-2013 |
20130220495 | ZIRCONIUM ALLOYS FOR A NUCLEAR FUEL CLADDING HAVING A SUPERIOR OXIDATION RESISTANCE IN A SEVERE REACTOR OPERATION CONDITION AND METHODS OF PREPARING A ZIRCONIUM ALLOY NUCLEAR CLADDING BY USING THEREOF - Disclosed are a zirconium alloy for a nuclear fuel cladding having a good oxidation resistance in a severe reactor operation condition and a method of preparing zirconium alloy nuclear fuel claddings by using thereof. The zirconium alloy includes 1.8 to 2.0 wt % of niobium (Nb); at least one element selected from iron (Fe), chromium (Cr) and copper (Cu); 0.1 to 0.15 wt % of oxygen (O); 0.008 to 0.012 wt % of silicon (Si) and a remaining amount of zirconium (Zr). The amount of Fe is 0.1 to 0.4 wt %, the amount of Cr is 0.05 to 0.2 wt %, and the amount of Cu is 0.03 to 0.2 wt %. A good oxidation resistance of the nuclear fuel cladding may be confirmed under a severe reactor operation condition at an accident condition as well as a normal operating condition of a reactor, thereby improving economic efficiency and safety. | 08-29-2013 |
20130299470 | Method for oxide dispersion strengthening of metallic material using laser - An oxide dispersion strengthening (ODS) method of a metallic material using a laser is provided, which includes melting a surface of a metallic matrix placed on a movable stage by irradiating a laser onto the surface (step 1), supplying an oxide dispersion strengthening (ODS) powder at a site of the matrix surface which is melt at step 1 (step 2), and cooling the matrix in which the ODS powder is supplied at step 2 (step 3). Because oxide particles are directly supplied into previously-made sheet or tube matrix, fabrication process is simplified, fabrication cost is reduced, and end product is fabricated efficiently. | 11-14-2013 |
20140205052 | Chelate Free Chemical Decontamination Reagent for Removal of the Dense Radioactive Oxide Layer on the Metal Surface and Chemical Decontamination Method Using the Same - A chemical decontamination reagent containing a reducing agent, a reductive metal ion, and an inorganic acid is provided to remove a radioactive oxide layer on a metal surface. The reagent can dissolve the radioactive oxide layer on the metal surface effectively at a relatively low temperature and enables a simple process of contacting the reagent to the radioactive oxide, thus economically effective in terms of cost and time required for the process. Since the decontamination does not use a conventional organic chelating agent such as oxalic acid, but the reducing agent as a main substance, the residuals of the reducing agent remained after decontamination can be decomposed and removed with an oxidizing agent. Due to the easy decomposition with the chemical decontamination reagent, secondary wastes can be minimized and the radionuclides remained in the decontamination reagent solution can be removed effectively. | 07-24-2014 |
20140378733 | Oxidation Decontamination Reagent for Removal of the Dense Radioactive Oxide Layer on the Metal Surface and Oxidation Decontamination Method Using the Same - The present invention provides an oxidative decontamination reagent for removal of the dense radioactive oxide layer on a metal surface, which comprises an oxidizing agent, a metal ion, and an inorganic acid. The oxidative decontamination reagent of the present invention is characteristically prepared by adding a metal ion to the conventional oxidative decontamination reagent containing an oxidizing agent and an inorganic acid. When the oxidative decontamination reagent of the present invention is used, electric potential of the metal parts of the primary system of the nuclear power plant can be regulated as passive potential owing to the added metal ion during the oxidative decontamination of the primary metal part of the nuclear power plant. Therefore, by maintaining electric potential of the metal part as passive potential, local corrosion can be inhibited and at the same time secondary waste can be significantly reduced. | 12-25-2014 |