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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">pimi</journal-id><journal-title-group><journal-title xml:lang="ru">Приборы и методы измерений</journal-title><trans-title-group xml:lang="en"><trans-title>Devices and Methods of Measurements</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2220-9506</issn><issn pub-type="epub">2414-0473</issn><publisher><publisher-name>BNTU</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.21122/2220-9506-2021-12-1-58-66</article-id><article-id custom-type="elpub" pub-id-type="custom">pimi-700</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>Методы измерений, контроля, диагностики</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>Methods of measurements, monitoring, diagnostics</subject></subj-group></article-categories><title-group><article-title>Оценка неравномерности упругих свойств листов из закрытоячеистых пенополиолефинов акустическим методом</article-title><trans-title-group xml:lang="en"><trans-title>Evaluation of Nonuniformity of Elastic Properties of Sheets Made from Closed-Сell Polyolefin Foams by Acoustic Method</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>Богдан</surname><given-names>О. П.</given-names></name><name name-style="western" xml:lang="en"><surname>Bogdan</surname><given-names>O. P.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Адрес для переписки: Богдан О.П. – Ижевский государственный технический университет имени М.Т. Калашникова, ул. Студенческая, 7, г. Ижевск 426069, Россия e-mail: Lelik_2005_05@mail.ru</p></bio><bio xml:lang="en"><p>Address for correspondence: Bogdan O.P. – Kalashnikov Izhevsk State Technical University, Studencheskaya str., 7, Izhevsk 426069, Udmurt Republic, Russia</p><p>e-mail: Lelik_2005_05@mail.ru</p></bio><email xlink:type="simple">Lelik_2005_05@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>Злобин</surname><given-names>Д. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Zlobin</surname><given-names>D. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p> ул. Студенческая, 7, г. Ижевск 426069</p></bio><bio xml:lang="en"><p>Studencheskaya str., 7, Izhevsk 426069</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Муравьева</surname><given-names>О. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Murav'eva</surname><given-names>O. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>ул. Студенческая, 7, г. Ижевск 426069; ул. им. Татьяны Барамзиной, 34, г. Ижевск 426067</p></bio><bio xml:lang="en"><p>Studencheskaya str., 7, Izhevsk 426069; Tatiana Baramzina str., 34, Izhevsk 426067, Udmurt Republic</p><p> </p></bio><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Молин</surname><given-names>С. М.</given-names></name><name name-style="western" xml:lang="en"><surname>Molin</surname><given-names>S. M.</given-names></name></name-alternatives><bio xml:lang="ru"><p>ул. им. Татьяны Барамзиной, 34, г. Ижевск 426067</p></bio><bio xml:lang="en"><p>Tatiana Baramzina str., 34, Izhevsk 426067, Udmurt Republic</p></bio><xref ref-type="aff" rid="aff-3"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Платунов</surname><given-names>А. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Platunov</surname><given-names>A. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p> ул. Студенческая, 7, г. Ижевск 426069</p></bio><bio xml:lang="en"><p>Studencheskaya str., 7, Izhevsk 426069</p></bio><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Ижевский государственный технический университет имени М.Т. Калашникова</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Kalashnikov Izhevsk State Technical University</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>Ижевский государственный технический университет имени М.Т. Калашникова; &#13;
Удмуртский федеральный исследовательский центр Уральского отделения Российской академии наук</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Kalashnikov Izhevsk State Technical University; &#13;
Udmurt Federal Research Center, Ural Branch of the Russian Academy of Sciences, Ural Branch of the Russian Academy of Sciences</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-3"><aff xml:lang="ru"><institution>Удмуртский федеральный исследовательский центр Уральского отделения Российской академии наук</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Udmurt Federal Research Center, Ural Branch of the Russian Academy of Sciences</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2021</year></pub-date><pub-date pub-type="epub"><day>19</day><month>03</month><year>2021</year></pub-date><volume>12</volume><issue>1</issue><fpage>58</fpage><lpage>66</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Богдан О.П., Злобин Д.В., Муравьева О.В., Молин С.М., Платунов А.В., 2021</copyright-statement><copyright-year>2021</copyright-year><copyright-holder xml:lang="ru">Богдан О.П., Злобин Д.В., Муравьева О.В., Молин С.М., Платунов А.В.</copyright-holder><copyright-holder xml:lang="en">Bogdan O.P., Zlobin D.V., Murav'eva O.V., Molin S.M., Platunov A.V.</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://pimi.bntu.by/jour/article/view/700">https://pimi.bntu.by/jour/article/view/700</self-uri><abstract><p>Широкое использование пенополиолефинов в стратегически важных отраслях промышленности обусловлено их высокими тепло-, звуко- и виброизоляционными свойствами. Целью работы являлась оценка неравномерности упругих свойств по площади листов пенополиолефинов различных типов с использованием акустического бесконтактного теневого амплитудного метода контроля и подтверждением методом структурного анализа.</p><p>Разработаны установка и новая методика бесконтактного акустического контроля листов из закрытоячеистых пенополиолефинов, основанная на регистрации амплитуды импульса, прошедшего сквозь лист, и позволяющая оценить неравномерность его упругих свойств в процессе сканирования. Исследования неравномерности упругих свойств проведены на листах из закрытоячеистых пенополиолефинов марки ISOLON 500 и ISOLON 300, различающиеся материалом и технологией изготовления (способ сшивки, метод и кратность вспенивания).</p><p>Показано, что на абсолютную амплитуду сигнала и её разброс относительно среднего значения влияет структура материала пенополиолефина и её неоднородность по площади исследуемого листа, определяемая технологией производства, что подтверждено визуально с использованием микроскопии. Исследования показали влияние на неравномерность показаний способа получения и кажущейся плотности материала. Показано, что наиболее неравномерные упругие свойства и структуру имеют листы из пенополиолефинов, полученных по технологии химической сшивки (неравномерность Δ составила 6,5 %). Из физически сшитых листов пенополиолефинов наиболее равномерными по структуре и упругим свойствам являются образцы, изготовленные из этиленвинилацетата с Δ = 3,8 %, а также листы с высокой кратностью вспенивания (Δ = 3,9 %). Неравномерность структуры исследованных листов пенополиолефинов подтверждена оптической микроскопией срезов в двух взаимно перпендикулярных направлениях.</p></abstract><trans-abstract xml:lang="en"><p>The widespread use of polyolefin foams in strategically important industries is due to their high thermal, sound and vibration insulation properties. The aim of the work was to evaluate the non-uniformity of elastic properties over the area of sheets of polyolefin foams of various types using the acoustic non-contact shadow amplitude method of testing and confirmation by the structural analysis method.</p><p>The article presents the developed installation and a new method of non-contact acoustic testing of sheets made of closed-cell polyolefin foams based on recording the amplitude of the pulse that passed through the sheet and allowing to assess to the unevenness of its elastic properties during scanning. Studies of uneven elastic properties were carried out on sheets of closed-cell polyolefin foams of the ISOLON 500 and ISOLON 300 brands which differ in material and manufacturing technology (technique of cross-linking, method and multiplicity of foaming).</p><p>It is shown that the absolute amplitude of the signal and its spread relative to the average value is affected by the structure of the foam polyolefin material and its heterogeneity over the area of the studied sheet determined by the production technology which is confirmed visually using microscopy.</p><p>Studies have shown the effect on the indications unevenness of the method of obtaining and the apparent density of the material. It is shown that the most uneven elastic properties and structure belong to sheets of polyolefin foam obtained by chemical cross-linking technology (the unevenness of Δ was 6.5 %). Among the physically cross-linked sheets of polyolefin foam the most uniform in structure and elastic properties are samples made of ethylene vinyl acetate with Δ = 3.8 %, as well as sheets with a high foaming rate (Δ = 3.9 %). The unevenness of structure of the studied sheets of polyolefin foams was confirmed by optical microscopy of sections in two mutually perpendicular directions.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>пенополиолефин</kwd><kwd>упругие свойства</kwd><kwd>акустический теневой метод</kwd><kwd>неравномерность</kwd><kwd>структура</kwd></kwd-group><kwd-group xml:lang="en"><kwd>polyolefin foam</kwd><kwd>elastic properties</kwd><kwd>acoustic shadow method</kwd><kwd>unevenness</kwd><kwd>structure</kwd></kwd-group><funding-group><funding-statement xml:lang="en">The study was carried out with the financial support of the grant of the Russian science foundation No. 18-79-10122 (methodology and experimental setup, research results) and the Kalashnikov Izhevsk State Technical University within the framework of the scientific  project No. PAV / 20-90-17 (structuroscopy of the studied samples) using the UNU "information and measurement complex for studies of acoustic properties of materials and products" (reg. number: 586308).</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">Kolbun N.V., Petrov S.N., Prudnik A.M. 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