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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">chemicallytech</journal-id><journal-title-group><journal-title xml:lang="en">Fine Chemical Technologies</journal-title><trans-title-group xml:lang="ru"><trans-title>Тонкие химические технологии</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2410-6593</issn><issn pub-type="epub">2686-7575</issn><publisher><publisher-name>MIREA – Russian Technological University (RTU MIREA).</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.32362/2410-6593-2021-16-1-55-66</article-id><article-id custom-type="elpub" pub-id-type="custom">chemicallytech-1686</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>CHEMISTRY AND TECHNOLOGY OF INORGANIC MATERIALS</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>ХИМИЯ И ТЕХНОЛОГИЯ НЕОРГАНИЧЕСКИХ МАТЕРИАЛОВ</subject></subj-group></article-categories><title-group><article-title>Neutron-diffraction study of the cubic-tetragonal phase structural transition in the single crystals of the solid solutions of zirconium and yttrium oxides</article-title><trans-title-group xml:lang="ru"><trans-title>Нейтронографическое исследование структурного перехода кубическая–тетрагональная фаза в монокристаллах твердых растворов оксида циркония с оксидом иттрия</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Сарин</surname><given-names>В. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Sarin</surname><given-names>V. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Сарин Виктор Анатольевич, к.ф.-м.н., ведущий инженер НИИ материалов твердотельной электроники. Scopus Author ID 7005455400</p><p>119454, Москва, пр-т Вернадского, д. 78</p></bio><bio xml:lang="en"><p>Viktor A. Sarin, Cand. Sci. (Phys.–Math.), Leading Engineer, Research Institute of Solid-State Electronics Materials. Scopus Author ID 7005455400</p><p>78, Vernadskogo pr., Moscow, 119454</p></bio><email xlink:type="simple">vic.fet@yandex.com</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-3990-9847</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Буш</surname><given-names>А. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Bush</surname><given-names>A. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Буш Александр Андреевич, д.т.н., профессор, директор НИИ материалов твердотельной электроники. Scopus Author ID 7201882802, Researcher ID R-2287-2016</p><p>119454, Москва, пр-т Вернадского, д. 78</p></bio><bio xml:lang="en"><p>Alexander A. Bush, Dr. Sci. (Eng.), Professor, Director of the Research Institute of Solid-State Electronics Materials. Scopus Author ID 7201882802, Researcher ID R-2287-2016</p><p>78, Vernadskogo pr., Moscow, 119454</p></bio><email xlink:type="simple">aabush@yandex.ru</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru">МИРЭА – Российский технологический университет<country>Россия</country></aff><aff xml:lang="en">MIREA – Russian Technological University<country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2021</year></pub-date><pub-date pub-type="epub"><day>18</day><month>03</month><year>2021</year></pub-date><volume>16</volume><issue>1</issue><fpage>55</fpage><lpage>66</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Sarin V.A., Bush A.A., 2021</copyright-statement><copyright-year>2021</copyright-year><copyright-holder xml:lang="ru">Сарин В.А., Буш А.А.</copyright-holder><copyright-holder xml:lang="en">Sarin V.A., Bush A.A.</copyright-holder><license license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.finechem-mirea.ru/jour/article/view/1686">https://www.finechem-mirea.ru/jour/article/view/1686</self-uri><abstract><sec><title>Objectives</title><p>Objectives. The determination of the phase relations, crystallographic characteristics, microstructure features, and atomic crystal structure of zirconium oxide crystals that are partially and completely stabilized by yttrium oxide additives, and the identification of the crystallographic and crystal-chemical correlations with the physicochemical properties of single crystals.</p></sec><sec><title>Methods</title><p>Methods. The neutron structure of the crystals was studied using the neutron time-of-flight and constant wavelength methods using a high-resolution Fourier diffractometer on the IBR-2 pulsed fast reactor and a four-circle neutron diffractometer “Syntex.” Single crystals were grown by directed crystallization from the melts of mixtures (1 − х)ZrO2 ∙хY2O3 , х = 0.03 and х = 0.12 with different growth rates (10 and 40 mm/h).</p></sec><sec><title>Results</title><p>Results. It was observed that when growing single crystals with x = 0.03–0.05, the crystal was stratified into cubic and tetragonal phases, and the ratio between the phases depended on the growth rate. At a growth rate of 40 mm/h, the content of the cubic phase was insignificant. In the crystals of partially stabilized zirconium dioxide (ZrO2) with the additions of 3 mol % Y2O3, the coherent coexistence of cubic and tetragonal phases was established, and the twin law for a tetragonal component (rotation of unit cell axis by 90° around the a (b) axis) that was observed during the phase transition from high-temperature cubic phase to tetragonal phase was determined. For the fully stabilized zirconium oxide of the cubic symmetry (with 12 mol % Y2O3), the 0.3 Å displacements of oxygen atoms from their partial structural positions in the directions [<xref ref-type="bibr" rid="cit100">100</xref>] and [<xref ref-type="bibr" rid="cit111">111</xref>] were determined. These displacements correlated with the directions of the ion transport.</p></sec><sec><title>Conclusions</title><p>Conclusions. Previous studies have shown that the ratio between the cubic and tetragonal phases of the single crystals of the ZrO2 –Y2O3 system depends on the growth rate of the single crystals. The content of Y2O3 in the cubic and tetragonal phases of a single crystal was determined using the non-destructive neutronography method on the same volume sample of a solid solution of this system. Moreover, the displacements of oxygen atoms from the main position of the crystal were determined.</p></sec></abstract><trans-abstract xml:lang="ru"><sec><title>Цели</title><p>Цели. Определение фазовых соотношений, кристаллографических характеристик, особенностей микроструктуры и атомно-кристаллической структуры кристаллов оксида циркония, частично и полностью стабилизированных добавками оксида иттрия, выявление кристаллографических и кристаллохимических корреляций с физико-химическими свойствами монокристаллов.</p></sec><sec><title>Методы</title><p>Методы. Нейтроноструктурные исследования кристаллов проведены методами времени пролета нейтронов и постоянной длины волны с использованием Фурье дифрактометра высокого разрешения на импульсном быстром реакторе ИБР-2 и четырехкружного нейтронного дифрактометра «Синтекс». Монокристаллы были выращены направленной кристаллизацией из расплавов смесей (1 – х)ZrO2 ∙хY2O3 , х = 0.03 и 0.12 с разными скоростями роста (10 и 40 мм/ч).</p></sec><sec><title>Результаты</title><p>Результаты. Установлено, что при выращивании монокристаллов с х = 0.03–0.05 происходит расслоение кристалла на кубическую и тетрагональную фазы, соотношение между которыми зависит от скорости выращивания. При скорости роста 40 мм/ч содержание кубической фазы незначительно. В кристаллах частично стабилизированного диоксида циркония ZrO2 (c добавками 3 mol % Y2O3) установлено когерентное сосуществование кубической и тетрагональной фаз и определен закон двойникования для тетрагональной компоненты (вращение осей элементарной ячейки на 90° вокруг осей a (b)), возникающего при фазовом переходе из высокотемпературной кубической фазы в тетрагональную. Для полностью стабилизированного диоксида циркония кубической симметрии (с 12 mol % Y2O3) определены смещения атомов кислорода на 0.3 Å из их частных структурных позиций в направлениях [<xref ref-type="bibr" rid="cit100">100</xref>] и [<xref ref-type="bibr" rid="cit111">111</xref>]. Эти смещения коррелирует с направлениями ионного транспорта.</p></sec><sec><title>Выводы</title><p>Выводы. Исследования показали, что соотношение между кубической фазой и тетрагональной фазой монокристаллов системы ZrO2 –Y2O3 зависит от скорости выращивания монокристаллов. На одном и том же объемном образце твердого раствора этой системы неразрушающим методом нейтронографии определено содержание Y2O3 и в кубической, и в тетрагональной фазе монокристалла. Определены смещения атомов кислорода из основной позиции кристалла.</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>стабилизированные оксидом иттрия кристаллы ZrO2</kwd><kwd>нейтроноструктурный анализ</kwd><kwd>микроструктура кристаллов</kwd><kwd>атомно-кристаллическая структура</kwd></kwd-group><kwd-group xml:lang="en"><kwd>yttrium oxide-stabilized ZrO2 crystals</kwd><kwd>neutron structure analysis</kwd><kwd>crystal microstructure</kwd><kwd>atomic crystal structure</kwd></kwd-group><funding-group xml:lang="ru"><funding-statement>Исследование выполнено при поддержке Министерства науки и высшего образования РФ: проект FSFZ-0706-2020-0022.</funding-statement></funding-group><funding-group xml:lang="en"><funding-statement>The study was supported by the Ministry of Science and Higher Education of the Russian Federation: project FSFZ-0706-2020-0022.</funding-statement></funding-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Nerst W. 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