powderИзвестия вузов. Порошковая металлургия и функциональные покрытияPowder Metallurgy аnd Functional Coatings (Izvestiya Vuzov. Poroshkovaya Metallurgiya i Funktsional'nye Pokrytiya)1997-308X2412-8767НИТУ "МИСИС"10.17073/1997-308X-2025-2-51-61powder-977Research ArticleТугоплавкие, керамические и композиционные материалыRefractory, Ceramic, and Composite MaterialsСмежность зерен карбида вольфрама и твердость наноструктурных и ультрамелкозернистых твердых сплавов WC–(Co)–VC–Cr3C2, полученных искровым плазменным и жидкофазным спеканиемGrain contiguity of tungsten carbide and hardness of nanostructured and ultrafine-grained WC–(Co)–VC–Cr3C2cemented carbides fabricated by spark plasma and liquid phase sinteringhttps://orcid.org/0000-0002-1216-4438ДворникМ. И.DvornikM. I.

Максим Иванович Дворник – к.т.н., ст. науч. сотрудник, зав. лабораторией порошковой металлургии

Россия, 680042, г. Хабаровск, ул. Тихоокеанская, 153

Maksim I. Dvornik – Cand. Sci. (Eng.), Senior Research Scientist, Head of the Powder Metallurgy Laboratories

153 Tikhookeanskaya Str., Khabarovsk 680042, Russia

maxxxx80@mail.ruhttps://orcid.org/0000-0002-4515-9109МихайленкоЕ. А.MikhailenkoE. A.

Елена Альбертовна Михайленко – к.ф.-м.н., ст. науч. сотрудник лаборатории порошковой металлургии

Россия, 680042, г. Хабаровск, ул. Тихоокеанская, 153

Elena A. Mikhailenko – Cand. Sci. (Phys.-Math.) Senior Research Scientist of the Laboratory of Powder Metallurgy

153 Tikhookeanskaya Str., Khabarovsk 680042, Russia

mea80@list.ruhttps://orcid.org/0000-0002-2441-6209ШичалинО. О.ShichalinO. O.

Олег Олегович Шичалин – к.х.н., ст. науч. сотрудник Института наукоемких технологий и передовых материалов

Россия, 690922, г. Владивосток, о. Русский, п. Аякс, 10

Oleg O. Shichalin – Cand. Sci. (Chem.) Senior Research Scientist of the Institute of Science-Intensive Technologies and Advanced Materials

10 Ajax Bay, Russky Island Vladivostok 690922, Russia

oleg_shich@mail.ruhttps://orcid.org/0000-0003-3944-3629БуравлевИ. Ю.BuravlevI. Yu.

Игорь Юрьевич Буравлев – к.х.н., зам. директора по развитию Института наукоемких технологий и передовых материалов

Россия, 690922, г. Владивосток, о. Русский, п. Аякс, 10

Igor Yu. Buravlev – Cand. Sci. (Chem.) Deputy Director for Deve­lopment of the Institute of Science-Intensive Technologies and Advan­ced Materials

10 Ajax Bay, Russky Island Vladivostok 690922, Russia

buravlev.i@gmail.comhttps://orcid.org/0000-0002-5636-4669БурковА. А.BurkovA. A.

Александр Анатольевич Бурков – к.ф.-м.н., ст. науч. сотрудник, зав. лабораторией физико-химических основ технологии материалов

Россия, 680042, г. Хабаровск, ул. Тихоокеанская, 153

Aleksandr A. Burkov – Cand. Sci. (Phys.-Math.), Senior Researcher, Head of the Laboratory of Physical and Chemical Fundamentals of Material’s Technology

153 Tikhookeanskaya Str., Khabarovsk 680042, Russia

burkovalex@mail.ruhttps://orcid.org/0000-0003-0198-0912ВласоваН. М.VlasovaN. M.

Нурия Мунавировна Власова – к.т.н., науч. сотрудник лаборатории порошковой металлургии

Россия, 680042, г. Хабаровск, ул. Тихоокеанская, 153

Nuriya M. Vlasova – Cand. Sci. (Eng.), Research Scientist of the Powder Metallurgy Laboratories

153 Tikhookeanskaya Str., Khabarovsk 680042, Russia

vlasova64@yandex.ruЧерняковЕ. В.ChernyakovE. V.

Евгений Витальевич Черняков – лаборант лаборатории порошковой металлургии

Россия, 680042, г. Хабаровск, ул. Тихоокеанская, 153

Evgeny V. Chernyakov – Laboratory Assistant of the Powder Metallurgy Laboratories

153 Tikhookeanskaya Str., Khabarovsk 680042, Russia

tchernyakoffevgeny@yandex.ruhttps://orcid.org/0000-0001-7672-1013ХеВ. К.KheV. K.

Владимир Канчерович Хе – мл. науч. сотрудник лаборатории конструкционных и инструментальных материалов

Россия, 680042, г. Хабаровск, ул. Тихоокеанская, 153

Vladimir K. Khe – Junior Research Scientist of the Laboratories of Construction and Instrumental Materials

153 Tikhookeanskaya Str., Khabarovsk 680042, Russia

khevlad@ya.ruhttps://orcid.org/0000-0002-1560-489XЧигринП. Г.ChigrinP. G.

Павел Геннадьевич Чигрин – к.х.н., ст. науч. сотрудник лаборатории физико-химических основ технологии материалов

Россия, 680042, г. Хабаровск, ул. Тихоокеанская, 153

Pavel G. Chigrin – Cand. Sci. (Chem.) Senior Research Scientist of the Laboratory of Physical and Chemical Fundamentals of Material’s Technology

153 Tikhookeanskaya Str., Khabarovsk 680042, Russia

pal_chig@mail.ruХабаровский федеральный исследовательский центр Дальневосточного отделения Российской академии наукРоссияKhabarovsk Federal Research Center of the Far Eastern Branch of the Russian Academy of SciencesRussian FederationДальневосточный федеральный университетРоссияFar Eastern Federal UniversityRussian Federation2025210420251925161Copyright © НИТУ "МИСИС", 20252025НИТУ "МИСИС"НИТУ "МИСИС"https://powder.misis.ru/jour/about/submissions#copyrightNoticehttps://powder.misis.ru/jour/article/view/977

Проведено исследование зависимостей смежности и твердости образцов наноструктурных и ультрамелкозернистых вольфрамокобальтовых твердых сплавов и карбида вольфрама, полученных методами искрового плазменного и жидкофазного спекания. Определены основные параметры микроструктуры: средний диаметр зерен WC, смежность зерна, средняя длина свободного пути в кобальте. Установлено, что средняя величина зерен WC в вольфрамокобальтовых металлокерамических твердых сплавах, полученных искровым плазменным спеканием, не превышает 0,2 мкм, поэтому их можно отнести к наноструктурным. Средний диаметр зерен WC в твердых сплавах, полученных жидкофазным или искровым плазменным спеканием, находится в пределах от 0,2 до 0,5 мкм, что позволяет классифицировать эти материалы как ультрамелкозернистые. Проанализирована пригодность существующих моделей, разработанных для средне- и мелкозернистых твердых сплавов, для описания зависимости смежности от объемной доли кобальта в полученных ультрамелкозернистых и наноструктурных материалах. Определено, что для спеченных в данной работе образцов подходит экспоненциальная зависимость. Проведен анализ применимости теоретической зависимости твердости от основных параметров микроструктуры. Твердость получаемых сплавов оказалась ниже, чем это предсказывает теоретическая закономерность, основанная на соотношении Холла–Петча. Наибольшей твердостью (HV = 2260 ± 30) из всех полученных образцов обладает наноструктурный сплав состава WC–5Co–0,4VC–0,4Cr3C2 , полученный искровым плазменным спеканием. Твердость ультрамелкозернистого спеченного карбида вольфрама оказалась немного ниже (HV = 2250 ± 20).

This study investigates the dependencies between contiguity and hardness in nanostructured and ultrafine-grained tungsten-cobalt cemented carbides and tungsten carbide samples fabricated using spark plasma sintering (SPS) and liquid phase sintering (LPS). The main microstructural parameters were determined: average WC grain size, grain contiguity, and mean free path in cobalt. The average WC grain size in tungsten-cobalt cemented carbides produced by spark plasma sintering does not exceed 0.2 µm, classifying them as nanostructured materials. In cemented carbides obtained by liquid phase sintering and tungsten carbide fabricated using spark plasma sintering, the average WC grain size ranges from 0.2 to 0.5 µm, which corresponds to ultrafine-grained materials. The applicability of existing models developed for medium- and fine-grained cemented carbides was analyzed to describe the dependencies of contiguity on the cobalt volume fraction in the obtained ultrafine-grained and nanostructured materials. It was found that an exponential dependence adequately describes this relationship for the samples sintered in this study. The applicability of the theoretical hardness dependence on key microstructural parameters was also analyzed. The hardness of the obtained alloys was lower than predicted by the theoretical dependence based on the Hall–Petch law. The highest hardness (HV = 2260 ± 30) among all the samples was observed in the nanostructured WC–5Co–0.4VC–0.4Cr3C2 alloy produced by spark plasma sintering. The hardness of ultrafine-grained sintered tungsten carbide was slightly lower (HV = 2250 ± 20).

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The authors declare that there are no conflicts of interest present.