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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">10.32362/2410-6593-2021-16-1-67-75</article-id><article-id custom-type="elpub" pub-id-type="custom">chemicallytech-1687</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>Chemical and technological aspects of increasing the functional characteristics of hard piezoceramics</article-title><trans-title-group xml:lang="ru"><trans-title>Химико-технологические аспекты повышения функциональных характеристик сегнетожесткой пьезокерамики</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-5416-9579</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Таланов</surname><given-names>М. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Talanov</surname><given-names>M. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Таланов Михаил Валерьевич, к.ф.-м.н., ведущий научный сотрудник. Scopus Author ID 53164920700, Researcher ID P-8971-2019</p><p>344090, г. Ростов-на-Дону, пр-т Стачки, д. 194</p></bio><bio xml:lang="en"><p>Mikhail V. Talanov, Cand. Sci. (Phys.–Math.), Leading Researcher. Scopus Author ID 53164920700, Researcher ID P-8971-2019</p><p>194, Stachki pr., Rostov-on-Don, 344090</p></bio><email xlink:type="simple">mvtalanov@gmail.com</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Мараховский</surname><given-names>М. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Marakhovskiy</surname><given-names>M. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Мараховский Михаил Алексеевич, к.т.н., начальник сектора. Scopus Author ID 57210826910</p><p>344090, г. Ростов-на-Дону, ул. Мильчакова, д. 10</p></bio><bio xml:lang="en"><p>Mikhail A. Marakhovskiy, Cand. Sci. (Eng.), Head of Sector. Scopus Author ID 57210826910</p><p>10, Milchakova ul, Rostov-on-Don, 344090</p></bio><email xlink:type="simple">marmisha@mail.ru</email><xref ref-type="aff" rid="aff-2"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>НИИ физики, Южный федеральный университет</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Research Institute of Physics, Southern Federal University</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>НКТБ Пьезоприбор, Южный федеральный университет</institution><country>Россия</country></aff><aff xml:lang="en"><institution>NKTB Piezopribor, Southern Federal University</institution><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>67</fpage><lpage>75</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Talanov M.V., Marakhovskiy M.A., 2021</copyright-statement><copyright-year>2021</copyright-year><copyright-holder xml:lang="ru">Таланов М.В., Мараховский М.А.</copyright-holder><copyright-holder xml:lang="en">Talanov M.V., Marakhovskiy M.A.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" 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/1687">https://www.finechem-mirea.ru/jour/article/view/1687</self-uri><abstract><sec><title>Objectives</title><p>Objectives. Ferroelectrically hard piezoelectric ceramics are in demand for high-power applications in piezotransformers, ultrasonic emitters, and piezo motors, which requires a combination of high piezoelectric characteristics and mechanical quality factors in it. The aim of this research was to reveal the main regularities in the microstructure and functional characteristic formation of ferroelectrically hard piezoceramics based on two widespread chemical systems, Pb(ZrxTi1-x)O3 and (Na1-xKx)NbO3, through various technological modes of production. In this study, two fundamentally different technological ways of forming a dense microstructure on the example of above systems have been employed to obtain the best set of dielectric, piezoelectric, and mechanical parameters for practical applications. In the case of lead-containing ceramics, various sintering technologies have been used, including conventional ceramic, hot pressing, and spark plasma sintering.</p></sec><sec><title>Methods</title><p>Methods. The microstructure of the piezoelectric ceramics was investigated using electron microscopy, and the functional characteristics were assessed in terms of mechanical and piezoelectric properties. The density values were determined by hydrostatic weighing in octane, the relative dielectric permittivity was measured using an LCR meter, and the values of the piezoelectric coefficient and mechanical quality factor were gathered using the resonance–antiresonance method.</p></sec><sec><title>Results</title><p>Results. This research has identified that spark plasma sintering technology makes it possible to obtain high-density samples, which contain a homogeneous microstructure and double the figure-of-merit values, for use in high-power piezoelectric devices that operate at piezoresonance frequencies. It also found that the addition of a small amount of CuNb2O6 (x = 0.025) to lead-free solid solutions leads to the formation of a liquid phase during sintering, thereby creating a compacted microstructure with relative density values (96%) that have practical limitations in conventional ceramic technology. An increase in both the piezoelectric and mechanical properties, which leads to a twofold increase in the values of the quality indicator, was also observed.</p></sec><sec><title>Conclusions</title><p>Conclusions. It is possible to increase, and even to double, the functional characteristics of both lead-containing and lead-free ferroelectrically hard piezoceramics by varying the technology used in the manufacturing process. By using spark plasma sintering technology with lead-containing ceramics, it is possible to reduce the optimum sintering temperature by 200 °C and the sintering time by more than 20 times, thus reducing production costs.</p></sec></abstract><trans-abstract xml:lang="ru"><sec><title>Цели</title><p>Цели. Сегнетожесткая пьезоэлектрическая керамика востребована при создании устройств, работающих в силовых режимах: пьезотрансформаторах, ультразвуковых излучателях и пьезодвигателях, что требует сочетания в ней высоких пьезоэлектрических характеристик и механической добротности. В этой работе на примере двух широко распространенных химических систем Pb(ZrxTi1-x)O3 и (Na1-xKx)NbO3 продемонстрированы принципиально различные химико-технологические пути формирования плотной микроструктуры и достижения наилучших, с точки зрения практических применений, наборов диэлектрических, пьезоэлектрических и механических параметров. В случае свинецсодержащей керамики были использованы различные технологии спекания: обычная керамическая, горячее прессование и искровое плазменное спекание. Для повышения функциональных характеристик бессвинцовой керамики был выбран путь, связанный с добавлением медьсодержащего компонента CuNb2O6 (x) к исходной системе ниобата натрия-калия. Целью настоящей работы стало выявление основных закономерностей формирования микроструктуры и функциональных характеристик сегнетожесткой керамики на основе систем Pb(ZrxTi1-x)O3 и (Na1-xKx)NbO3, при вариации технологических режимов их изготовления.</p></sec><sec><title>Материалы</title><p>Материалы. Микроструктура пьезоэлектрической керамики исследовалась методом электронной микроскопии, а функциональные характеристики оценивались по показателям механических и пьезоэлектрических свойств. Значения плотности определялись методом гидростатического взвешивания в октане, относительная диэлектрическая проницаемость была измерена с помощью LCR-метра, а значения пьезоэлектрического коэффициента и механической добротности установлены на основании резонансно-антирезонансного метода.</p></sec><sec><title>Результаты</title><p>Результаты. Установлено, что применение технологии искрового плазменного спекания позволяет получить высокоплотные образцы свинецсодержащей керамики с однородной микроструктурой и более чем в два раза возросшими значениями показателя качества (figure-of-merit) для ее использования в устройствах силовой пьезотехники, работающих на частотах пьезорезонанса. Обнаружено, что добавка небольшого количества CuNb2O6 (x = 0.025) к бессвинцовым твердым растворам приводит к образованию в процессе спекания жидкой фазы, в результате чего формируется уплотненная микроструктура с практически предельными для обычной керамической технологии значениями относительной плотности (96%). Наблюдается возрастание как пьезоэлектрических, так и механических свойств, что приводит к двукратному повышению значений показателя качества.</p></sec><sec><title>Выводы</title><p>Выводы. Вариация технологических режимов изготовления как свинецсодержащей, так и бессвинцовой сегнетожесткой пьезокерамики позволяет существенно (в два раза) повысить ее функциональные характеристики. Использование метода искрового плазменного спекания при изготовлениии свинецсодержащей керамики способствует сокращению как оптимальной температуры процесса на 200 °С, так и продолжительности изотермической выдержки более чем в 20 раз. Такой прием существенно снижает производственные затраты.</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>пьезокерамика</kwd><kwd>технология спекания</kwd><kwd>искровое плазменное спекание</kwd><kwd>микроструктура</kwd><kwd>пьезоэлектрические свойства</kwd><kwd>механическая добротность</kwd><kwd>жидкие фазы</kwd><kwd>показатель качества</kwd></kwd-group><kwd-group xml:lang="en"><kwd>piezoceramics</kwd><kwd>sintering technology</kwd><kwd>spark plasma sintering</kwd><kwd>microstructure</kwd><kwd>piezoelectric properties</kwd><kwd>mechanical quality factor</kwd><kwd>liquid phases</kwd><kwd>figure-of-merit</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">Авторы выражают благодарность Г.М. Константинову за получение снимков микроструктуры бессвинцовой керамики. Исследование выполнено при финансовой поддержке Министерства науки и высшего образования РФ (Государственное задание в сфере научной деятельности, научный проект № 0852-2020-0032), (BAZ0110/20-3-07IF).</funding-statement><funding-statement xml:lang="en">The authors are grateful to G.M. Konstantinov for obtaining microstructure images of lead-free ceramics. The study was carried out with the financial support of the Ministry of Science and Higher Education of the Russian Federation (State task in the field of scientific activity, scientific project No. 0852-2020-0032), (BAZ0110/20-3-07IF).</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">Jaffe B., Cook W.R., Jaffe H. Piezoelectric Ceramics. New York: Academic Press; 1971. 317 p.</mixed-citation><mixed-citation xml:lang="en">Jaffe B., Cook W.R., Jaffe H. Piezoelectric Ceramics. 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