US 12,482,575 B2
Method of manufacturing a nuclear fuel element end plug which contains ß-SiC, Al2O3, and Y2O3
Leonid Aleksandrovich Karpyuk, Moscow (RU); Vladislav Konstantinovich Orlov, Moscow (RU); Sergey Igorevich Ivanov, Moscow (RU); Alexey Vladimirovich Glebov, Moscow (RU); Fyodor Viktorovich Makarov, Krasnogorsk District (RU); Roman Gennadyevich Zakharov, Moscow (RU); Ivan Alexandrovich Dzyubinsky, Moscow (RU); Alexander Pavlovich Ponomarenko, Moscow (RU); and Dmitry Vladimirovich Kuznetsov, Moscow (RU)
Assigned to BOCHVAR HIGH-TECHNOLOGY RESEARCH INSTITUTE FOR INORGANIC MATERIALS, Moscow (RU)
Appl. No. 17/620,731
Filed by BOCHVAR HIGH-TECHNOLOGY RESEARCH INSTITUTE FOR INORGANIC MATERIALS, Moscow (RU)
PCT Filed Dec. 29, 2020, PCT No. PCT/RU2020/000771
§ 371(c)(1), (2) Date Dec. 19, 2021,
PCT Pub. No. WO2022/103296, PCT Pub. Date May 19, 2022.
Claims priority of application No. 2020136805 (RU), filed on Nov. 10, 2020.
Prior Publication US 2022/0415526 A1, Dec. 29, 2022
Int. Cl. G21C 21/00 (2006.01); G21C 3/10 (2006.01); G21C 3/07 (2006.01)
CPC G21C 21/00 (2013.01) [G21C 3/10 (2013.01); G21C 3/07 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A method for manufacturing an end plug for sealing a composite tubular ceramic cladding of a fuel element of a nuclear reactor, comprising the steps of:
preparing a powder mixture from β-SiC powder, Al2O3 powder and Y2O3 powder, which are taken in the following quantities, wt %:
β-SiC with particles of 0.95 microns—10.59,
β-SiC with particles of 5.19 microns—77.91,
Al2O3 with particles of 1.52 microns—10.0,
Y2O3 with particles of 1.01 microns—the rest;
hot pressing of the powder mixture with the use of upper and lower punches and a mold with mold cells,
wherein each mold cell has a shape and dimensions corresponding to an end plug having a first part and a second part,
wherein the first and second parts are coaxial cylinders having different diameters,
wherein the step of hot pressing comprises the steps of:
arranging the lower punches into inner cavities of the mold cells,
loading the powder mixture into the inner cavities and onto the lower punches,
putting the upper punches into the mold cells over the powder mixture,
holding the powder mixture without heating at the pressure of 1 Pa for more than 12 hours,
pressing the powder mixture in the mold cells with the use of the upper punches,
sintering at the temperature of 1850 degrees C. in an inert gas atmosphere or in vacuum at the pressure of 0.1 MPa, and
having the holding duration in the sintering mode be 120 minutes; and
ejecting finished end plugs from the mold cells.