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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">blackmet</journal-id><journal-title-group><journal-title xml:lang="ru">Известия высших учебных заведений. Черная Металлургия</journal-title><trans-title-group xml:lang="en"><trans-title>Izvestiya. Ferrous Metallurgy</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">0368-0797</issn><issn pub-type="epub">2410-2091</issn><publisher><publisher-name>National University of Science and Technology "MISIS"</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.17073/0368-0797-2022-12-879-886</article-id><article-id custom-type="elpub" pub-id-type="custom">blackmet-2453</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>МАТЕРИАЛОВЕДЕНИЕ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>MATERIAL SCIENCE</subject></subj-group></article-categories><title-group><article-title>Деформация и разрушение Cr – Mn – C – N стали в литом состоянии</article-title><trans-title-group xml:lang="en"><trans-title>Strain and fracture of Cr – Mn – C – N steel in cast state</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-2195-4906</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Дерюгин</surname><given-names>Е. Е.</given-names></name><name name-style="western" xml:lang="en"><surname>Deryugin</surname><given-names>E. E.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Евгений Евгеньевич Дерюгин, д.ф.-м.н., профессор, ведущий научный сотрудник</p><p>Россия, 634055, Томск, пр. Академичес­кий, 2/4</p></bio><bio xml:lang="en"><p>Evgenii E. Deryugin, Dr. Sci. (Phys.–Math.), Prof., Leading Researcher</p><p>2/4 Akademiches­kii Ave., Tomsk 634055, Russian Federation</p></bio><email xlink:type="simple">dee@ispms.tsc.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-5179-1955</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Наркевич</surname><given-names>Н. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Narkevich</surname><given-names>N. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Наталья Аркадьевна Наркевич, к.т.н., доцент, старший научный сотрудник</p><p>Россия, 634055, Томск, пр. Академичес­кий, 2/4</p></bio><bio xml:lang="en"><p>Natal’ya A. Narkevich, Cand. Sci. (Eng.), Assist. Prof., Senior Researcher</p><p>2/4 Akademiches­kii Ave., Tomsk 634055, Russian Federation</p></bio><email xlink:type="simple">natnark@list.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-0880-2898</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Гоморова</surname><given-names>Ю. Ф.</given-names></name><name name-style="western" xml:lang="en"><surname>Gomorova</surname><given-names>Yu. F.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Юлия Федоровна Гоморова, к.т.н., научный сотрудник</p><p>Россия, 634055, Томск, пр. Академичес­кий, 2/4</p></bio><bio xml:lang="en"><p>Yulia F. Gomorova, Cand. Sci. (Eng.), Research Associate</p><p>2/4 Akademiches­kii Ave., Tomsk 634055, Russian Federation</p></bio><email xlink:type="simple">gomjf@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 Сибирского отделения РАН</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Institute of Strength Physics and Materials Science, Siberian Branch of the Russian Academy of Sciences</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2022</year></pub-date><pub-date pub-type="epub"><day>31</day><month>12</month><year>2022</year></pub-date><volume>65</volume><issue>12</issue><fpage>879</fpage><lpage>886</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Дерюгин Е.Е., Наркевич Н.А., Гоморова Ю.Ф., 2023</copyright-statement><copyright-year>2023</copyright-year><copyright-holder xml:lang="ru">Дерюгин Е.Е., Наркевич Н.А., Гоморова Ю.Ф.</copyright-holder><copyright-holder xml:lang="en">Deryugin E.E., Narkevich N.A., Gomorova Y.F.</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://fermet.misis.ru/jour/article/view/2453">https://fermet.misis.ru/jour/article/view/2453</self-uri><abstract><p>Исследовано влияние граничных условий и скорости нагружения на деформационное поведение и разрушение стали на основе Cr – Mn – С – N аустенита в литом состоянии без дополнительной термической обработки. Закономерности деформации и разрушения стали проанализированы на основе данных испытаний на трехточечный изгиб образцов квадратного сечения с надрезом и без надреза, положенных ребром на опоры. Такое нетрадиционное расположение образца на опорах позволило обнаружить помимо начальной стадии упругой деформации стали еще две стадии развития деформации под действием внешней приложенной силы: стадию нелинейной деформации и стадию прерывистой деформации, предшествующей моменту разрушения образца. Показано, что с увеличением скорости нагружения сопротивление разрушению и протяженность стадии нелинейной деформации образца с надрезом увеличивается, а протяженность стадии прерывистой деформации уменьшается. Образец без надреза имеет продолжительную стадию нелинейной деформации и проявляет максимальную прочность при отсутствии стадии прерывистого течения. Завершение стадии нелинейной деформации соответствует моменту разрушения образца. Характерным свойством литой стали при заданных условиях нагружения является то, что разрушение образца совершается хрупко, несмотря на продолжительную стадию нелинейной деформации. Структурные металлографические и дифрактометрические исследования показали, что во всех испытаниях разрушение стали происходит хрупко без следов пластической деформации. Стадия нелинейной деформации стали определяется не дислокационной пластической деформацией, а механизмом γ → αʹ-превращения в аустенитных прослойках между нитридными и карбидными частицами под действием внешней приложенной силы. Стадия прерывистой деформации стали связана с процессом стабильного распространения трещины по поперечному сечению образца.</p></abstract><trans-abstract xml:lang="en"><p>The paper studies the influence of boundary conditions and the loading rate on the strain behavior and fracture of Cr – Mn – C – N austenitic steel in the cast state without additional heat treatment. Regularities of steel strain and fracture were analyzed on the basis of three-point bending test data of square-section samples with and without a notch, placed with a rib on supports. In addition to the initial stage of the steel elastic strain, this unconventional arrangement of the sample on supports enabled the detection of two more stages of strain development under the effect of an external applied force: the stage of nonlinear strain and the stage of discontinuous strain preceding the moment of sample failure. As the loading rate increases, it was demonstrated that the fracture resistance and the extent of the nonlinear strain stage of the sample with a notch decreases, and the extent of the discontinuous strain stage increases. The sample without a notch has a prolonged nonlinear strain stage and exhibits maximum strength in the absence of the discontinuous stage. The end of the nonlinear strain stage corresponds to the moment of sample failure. A characteristic property of cast steel under the given loading conditions is that the fracture of the sample is brittle, despite the prolonged stage of non-linear strain. Structural metallographic and diffractometric studies have shown that in all tests the steel fracture is brittle with-out traces of plastic yield. The nonlinear strain stage of steel is determined not by dislocation plastic yield, but by the mechanism of γ → αʹ transformation in austenitic interlayers between nitride and carbide particles under the effect of an external applied force. The discontinuous strain stage of steel is associated with the process of stable crack propagation across the sample.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>литая Cr – Mn – C – N сталь</kwd><kwd>дендритная структура</kwd><kwd>прерывистый распад</kwd><kwd>нитриды</kwd><kwd>испытания на изгиб</kwd><kwd>разрушение</kwd></kwd-group><kwd-group xml:lang="en"><kwd>cast Cr – Mn – C – N steel</kwd><kwd>dendritic structure</kwd><kwd>discontinuous decay</kwd><kwd>nitrides</kwd><kwd>bending test</kwd><kwd>fracture</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">Работа выполнена в рамках государственного задания ИФПМ Сибирского отдедения РАН (тема FWRW-2021-0009), а также при поддержке Российского научного фонда, грант № 22-29-00438.</funding-statement><funding-statement xml:lang="en">The work was performed within the framework of the state task of the Institute of Strength Physics and Materials Science, Siberian Branch of the Russian Academy of Sciences, project FWRW-2021-0009 and supported by the Russian Science Foundation, grant RSF 22-29-00438.</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">Berns H., Gavriljuk V., Riedner S., Tyshchenko A. 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