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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="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">cvmet</journal-id><journal-title-group><journal-title xml:lang="ru">Известия вузов. Цветная металлургия</journal-title><trans-title-group xml:lang="en"><trans-title>Izvestiya. Non-Ferrous Metallurgy</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">0021-3438</issn><issn pub-type="epub">2412-8783</issn><publisher><publisher-name>НИТУ "МИСИС"</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.17073/0021-3438-2022-1-39-51</article-id><article-id custom-type="elpub" pub-id-type="custom">cvmet-1324</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="ru"><subject>Обработка металлов давлением</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>Pressure Treatment of Metals</subject></subj-group></article-categories><title-group><article-title>ВЛИЯНИЕ МНОГОПРОХОДНОЙ ФРИКЦИОННОЙ ПЕРЕМЕШИВАЮЩЕЙ ОБРАБОТКИ НА ФОРМИРОВАНИЕ МИКРОСТРУКТУРЫ И МЕХАНИЧЕСКИЕ СВОЙСТВА СПЛАВА ВТ6</article-title><trans-title-group xml:lang="en"><trans-title>Influence of multi-pass friction stir processing on the formation of microstructure and mechanical properties of Ti6Al4V alloy</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>Зыкова</surname><given-names>А. П.</given-names></name><name name-style="western" xml:lang="en"><surname>Zykova</surname><given-names>A. P.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Зыкова А.П. – канд. физ.-мат. наук, ст. науч. сотр. лаборатории структурного дизайна перспективных материалов</p><p>634055, г. Томск, пр. Академический, 2/4</p></bio><bio xml:lang="en"><p>Zykova A.P. – Cand. Sci. (Phys.-Math.), researcher of the Laboratory of structural design and advanced materials</p><p>634055, Russia, Tomsk, Akademicheskii pr., 2/4</p></bio><email xlink:type="simple">zykovaap@mail.ru</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>Воронцов</surname><given-names>А. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Vorontsov</surname><given-names>A. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Воронцов А.В. – аспирант, мл. науч. сотр. лаборатории локальной металлургии в аддитивных технологиях</p><p>634055, г. Томск, пр. Академический, 2/4</p></bio><bio xml:lang="en"><p>Vorontsov A.V. – postgraduate student, junior researcher of the Laboratory of local metallurgy in additive technologies  </p><p>634055, Russia, Tomsk, Akademicheskii pr., 2/4</p></bio><email xlink:type="simple">vav@ispms.ru</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>Чумаевский</surname><given-names>А. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Chumaevskii</surname><given-names>A. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Чумаевский А.В. – канд. техн. наук, науч. сотр. лаборатории локальной металлургии в аддитивных технологиях</p><p>634055, г. Томск, пр. Академический, 2/4</p></bio><bio xml:lang="en"><p>Chumaevskii А.V. – Cand. Sci. (Eng.), researcher of the Laboratory of local metallurgy in additive technologies</p><p>634055, Russia, Tomsk, Akademicheskii pr., 2/4</p></bio><email xlink:type="simple">tch7av@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>Гурьянов</surname><given-names>Д. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Gurianov</surname><given-names>D. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Гурьянов Д.А. – аспирант, мл. науч. сотр. лаборатории локальной металлургии в аддитивных технологиях</p><p>634055, г. Томск, пр. Академический, 2/4</p></bio><bio xml:lang="en"><p>Gurianov D.A. – postgraduate student, junior researcher of the Laboratory of local metallurgy in additive technologies</p><p>634055, Russia, Tomsk, Akademicheskii pr., 2/4</p></bio><email xlink:type="simple">desa-93@mail.ru</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>Гусарова</surname><given-names>А. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Gusarova</surname><given-names>A. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Гусарова А.В. – аспирант, мл. науч. сотр. лаборатории локальной металлургии в аддитивных технологиях</p><p>634055, г. Томск, пр. Академический, 2/4</p></bio><bio xml:lang="en"><p>Gusarova A.V. – postgraduate student, junior researcher of the Laboratory of local metallurgy in additive technologies</p><p>634055, Russia, Tomsk, Akademicheskii pr., 2/4</p></bio><email xlink:type="simple">gusarova@ispms.ru</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>Савченко</surname><given-names>Н. Л.</given-names></name><name name-style="western" xml:lang="en"><surname>Savchenko</surname><given-names>N. L.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Савченко Н.Л. – докт. техн. наук, вед. науч. сотр. лаборатории контроля качества материалов и конструкций</p><p>634055, г. Томск, пр. Академический, 2/4</p></bio><bio xml:lang="en"><p>Savchenko N.L. – Dr. Sci. (Eng.), leading researcher of the Laboratory for quality control of materials and structures</p><p>634055, Russia, Tomsk, Akademicheskii pr., 2/4</p></bio><email xlink:type="simple">savnick@ispms.ru</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>Колубаев</surname><given-names>Е. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Kolubaev</surname><given-names>E. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Колубаев Е.А. – докт. техн. наук, зав. лабораторией локальной металлургии в аддитивных технологиях</p><p>634055, г. Томск, пр. Академический, 2/4</p></bio><bio xml:lang="en"><p>Kolubaev E.A. – Dr. Sci. (Eng.), head of the Laboratory of local metallurgy in additive technologies</p><p>634055, Russia, Tomsk, Akademicheskii pr., 2/4</p></bio><email xlink:type="simple">eak@ispms.ru</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Институт физики прочности и материаловедения (ИФПМ) СО РАН</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Institute of Strength Physics and Materials Science of Siberian Branch of Russian Academy of Sciences (ISPMS SB RAS)</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2022</year></pub-date><pub-date pub-type="epub"><day>19</day><month>02</month><year>2022</year></pub-date><volume>28</volume><issue>1</issue><fpage>39</fpage><lpage>51</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Зыкова А.П., Воронцов А.В., Чумаевский А.В., Гурьянов Д.А., Гусарова А.В., Савченко Н.Л., Колубаев Е.А., 2022</copyright-statement><copyright-year>2022</copyright-year><copyright-holder xml:lang="ru">Зыкова А.П., Воронцов А.В., Чумаевский А.В., Гурьянов Д.А., Гусарова А.В., Савченко Н.Л., Колубаев Е.А.</copyright-holder><copyright-holder xml:lang="en">Zykova A.P., Vorontsov A.V., Chumaevskii A.V., Gurianov D.A., Gusarova A.V., Savchenko N.L., Kolubaev E.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://cvmet.misis.ru/jour/article/view/1324">https://cvmet.misis.ru/jour/article/view/1324</self-uri><abstract><p>Фрикционная перемешивающая обработка (ФПО) – это передовая технология поверхностного изменения микроструктуры металлов и сплавов для улучшения механических и эксплуатационных свойств. Предыдущие работы по обработке титановых сплавов показали, что варьирование технологических параметров ФПО (таких, как скорость вращения, скорость перемещения и сила прижима инструмента) значительно влияет на эволюцию микроструктуры и механические свойства ВТ6. Однако влияние многопроходной ФПО на сплав ВТ6 не было изучено. Поэтому в работе исследовано влияние четырехпроходной ФПО титанового сплава ВТ6 на эволюцию микроструктуры, механические свойства и износостойкость этого сплава. Анализ микроструктуры показал, что зоне перемешивания формируется неоднородная микроструктура с динамически рекристаллизованными равноосными α-зернами, β-зернами и β-областями с α-фазой игольчатого и ламинарного типов, что связано с температурным градиентом зоны перемешивания в процессе ФПО. Установлено, что с увеличением количества проходов ФПО до 3 раз наблюдается повышение предела прочности (до 1173 МПа) и износостойкости (на 33 %). Улучшение предела прочности образцов после 3 проходов ФПО обусловлено уменьшением размеров зерен в зоне перемешивания на 88 % по сравнению с исходным ВТ6. Показано, что после 4 проходов ФПО в зоне перемешивания происходит увеличение размеров зерен и понижение предела прочности до 686 МПа, что связано с образованием крупных дефектов по контуру потоков металла. При этом износостойкость ВТ6 после 4 проходов ФПО возрастает на 39 % по сравнению с исходным материалом.</p></abstract><trans-abstract xml:lang="en"><p>Friction stir processing (FSP) is an advanced technology for altering the surface microstructure of metals and alloys to improve mechanical and performance properties. Previous research on titanium alloy processing showed that varying the FSP process parameters (such as rotational speed, movement speed and tool contact force) significantly affects the Ti–6Al–4V microstructure evolution and mechanical properties. However, the effect of multipass FSP on the Ti–6Al–4V alloy was not studied. Therefore, this paper studies the effect of four-pass FSP of the Ti–6Al–4V titanium alloy on the microstructure evolution, mechanical properties and wear resistance of this alloy. Microstructure analysis showed that the stirring zone forms heterogeneous microstructure with dynamically recrystallized equiaxed α grains, β grains and β areas with α phase of needle and laminar type, which is associated with the stirring zone temperature gradient during FSP. It was found that an increase in the number of FSP passes up to 3 times improves the ultimate tensile strength (up to 1173 MPa) and wear resistance (by 33 %). The improved ultimate tensile strength of samples after 3 FSP passes is caused by grain size reduction in the stirring zone by 88 % compared to the initial Ti–6Al–4V alloy. It was shown that after 4 FSP passes the grain size increases and the ultimate tensile strength decreases to 686 MPa in the stirring zone, which is associated with large defects formed along the contour of metal flows. At the same time the Ti–6Al–4V wear resistance after 4 FSP passes increases by 39 % compared to the raw material.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>фрикционная перемешивающая обработка</kwd><kwd>титановые сплавы</kwd><kwd>фазовые превращения</kwd><kwd>размер зерна</kwd><kwd>износостойкость</kwd><kwd>предел прочности</kwd></kwd-group><kwd-group xml:lang="en"><kwd>friction stirring processing</kwd><kwd>titanium alloys</kwd><kwd>phase transformations</kwd><kwd>grain size</kwd><kwd>wear resistance</kwd><kwd>ultimate strength</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">Работа выполнена в рамках государственного задания ИФПМ СО РАН, тема номер FWRW-2021-0012</funding-statement><funding-statement xml:lang="en">The work was performed according to the Government research assignment for ISPMS SB RAS, project FWRW-2021-0012</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">Chan K.S., Koike M., Okabe T. 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