zldmЗаводская лаборатория. Диагностика материаловIndustrial laboratory. Diagnostics of materials1028-68612588-0187ООО «Издательство «ТЕСТ-ЗЛ»10.26896/1028-6861-2026-92-5-28-34zldm-2827Research ArticleИССЛЕДОВАНИЕ СТРУКТУРЫ И СВОЙСТВ. ФИЗИЧЕСКИЕ МЕТОДЫ ИССЛЕДОВАНИЯ И КОНТРОЛЯTESTING OF STRUCTURE AND PARAMETERS. PHYSICAL METHODS OF TESTING AND QUALITY CONTROLИсследование влияния зерен аномального роста на механические свойства керамик на основе оксида алюминияResearch of effect of abnormally growth grains on mechanical properties of aluminum oxide-based ceramicsИсуповаЕ. А.IsupovaE. A.

Евгения Александровна Исупова

603022, г. Нижний Новгород, просп. Гагарина, д. 23

Evgeniya A. Isupova

23, prosp. Gagarina, Nizhny Novgorod, 603022

ЛанцевЕ. А.LantsevE. A.

Евгений Андреевич Ланцев

603022, г. Нижний Новгород, просп. Гагарина, д. 23

Evgeni A. Lantsev

23, prosp. Gagarina, Nizhny Novgorod, 603022

БолдинМ. С.BoldinM. S.

Максим Сергеевич Болдин

603022, г. Нижний Новгород, просп. Гагарина, д. 23

Maksim S. Boldin

23, prosp. Gagarina, Nizhny Novgorod, 603022

boldin@nifti.unn.ruМурашовА. А.MurashovA. A.

Артём Александрович Мурашов

603022, г. Нижний Новгород, просп. Гагарина, д. 23

Artem A. Murashov

23, prosp. Gagarina, Nizhny Novgorod, 603022

Национальный исследовательский нижегородский государственный университет им. Н. И. ЛобачевскогоРоссияLobachevsky UniversityRussian Federation2026270520269252834Copyright © Исупова Е.А., Ланцев Е.А., Болдин М.С., Мурашов А.А., 20262026Исупова Е.А., Ланцев Е.А., Болдин М.С., Мурашов А.А.Isupova E.A., Lantsev E.A., Boldin M.S., Murashov A.A.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://www.zldm.ru/jour/article/view/2827

Максимальными механическими свойствами характеризуются образцы керамик из оксида алюминия с субмикронной равноосной зеренной микроструктурой. Однако при определенных соотношениях доли мелких и крупных зерен наличие в структуре крупных зерен аномального роста можно рассматривать не как дефект, а как упрочняющую фазу, позволяющую достигать более высоких механических характеристик, в частности высокой прочности на изгиб. Цель работы — исследование влияния объемной доли аномально крупных зерен на прочность и трещиностойкость керамики на основе оксида алюминия. Формирование зерен аномального роста проходило при свободном спекании субмикронного порошка α-Al2O3. Показано, что при спекании в условиях постоянной скорости нагрева до относительной плотности ~97 % структура материала состоит из равноосных зерен (размер ~0,7 мкм) и зерен аномального роста (5 % об., размер более 10 мкм). Варьированием параметров процесса спекания получали керамики, различающиеся объемной долей зерен аномального роста. Установлено, что увеличение доли зерен аномального роста с 5 до 15 % об. позволяет повысить прочность и трещиностойкость керамики более чем в 1,5 раза. Улучшение механических свойств достигается за счет отклонения траектории развивающейся трещины от прямолинейной путем огибания аномально крупных зерен. Полученные результаты и предложенный подход могут быть использованы при совершенствовании методики для повышения механических свойств керамик, полученных свободным спеканием.

Alumina ceramic specimens with a submicron equiaxed grain microstructure exhibit the highest mechanical performance. However, for certain ratios of fine and coarse grains, the presence of abnormally grown grains may be regarded not as a defect but as a strengthening phase, enabling improved properties, in particular high flexural strength. The aim of this work is to investigate the effect of the volume fraction of abnormally large grains on the strength and fracture toughness of alumina-based ceramics. Abnormal grain growth was achieved during pressureless sintering of submicron α-Al2O3 powder. It is shown that, under sintering at a constant heating rate up to a relative density of ~97%, the microstructure consists of equiaxed grains (size ~0.7 μm) and abnormally grown grains (5 vol. %, size >10 μm). By varying the sintering parameters, ceramics with different volume fractions of abnormally grown grains were produced. Increasing the fraction of abnormally grown grains from 5 to 15 vol. % increases the strength and fracture toughness by more than 1.5 times. The improved mechanical properties are attributed to deflection of the crack path from a straight trajectory as the crack bypasses abnormally large grains. The results obtained and the proposed approach may be used to optimise pressureless sintering routes for enhancing the mechanical properties of ceramics.

оксид алюминиямикроструктураспеканиемеханические свойстваaluminum oxidemicrostructuresinteringmechanical propertiesРабота выполнена при поддержке Российского научного фонда (грант № 20-73-10113-П).ReferencesAbyzov A. M. Aluminum oxide and alumina ceramics (review). Part 1. Properties of Al2O3 and industrial production of dispersed Al2O3 / Nov. Ogneupory. 2019. No. 1. P. 16 – 23 [in Russian]. DOI: 10.17073/1683-4518-2019-1-16-23Abyzov A. M. Aluminum oxide and alumina ceramics (review). Part 1. Properties of Al2O3 and industrial production of dispersed Al2O3 / Nov. Ogneupory. 2019. No. 1. P. 16 – 23 [in Russian]. DOI: 10.17073/1683-4518-2019-1-16-23Yang S., Dai Y., Han N., et al. Microstructure and hardness of two-step reverse-polarity flash sintered high-purity Al2O3 ceramics / Ceram. Int. A. 2024. Vol. 50. No. 21. P. 41664 – 41672. DOI: 10.1016/j.ceramint.2024.08.017Yang S., Dai Y., Han N., et al. Microstructure and hardness of two-step reverse-polarity flash sintered high-purity Al2O3 ceramics / Ceram. Int. A. 2024. Vol. 50. No. 21. P. 41664 – 41672. DOI: 10.1016/j.ceramint.2024.08.017Li W., Shen Y., Li D., et al. Preparation of 99.6% alumina ceramic substrates with high thermal conductivity by tape casting and warm pressing process / Ceram. Int. 2025. Vol. 51. No. 4. P. 5000 – 5010. DOI: 10.1016/j.ceramint.2024.11.471Li W., Shen Y., Li D., et al. Preparation of 99.6% alumina ceramic substrates with high thermal conductivity by tape casting and warm pressing process / Ceram. Int. 2025. Vol. 51. No. 4. P. 5000 – 5010. DOI: 10.1016/j.ceramint.2024.11.471Ruys A. Alumina ceramics biomedical and clinical applications. — Duxford: Woodhead Publishing, 2019. — 558 p. DOI: 10.1016/c2017-0-01189-8Ruys A. Alumina ceramics biomedical and clinical applications. — Duxford: Woodhead Publishing, 2019. — 558 p. DOI: 10.1016/c2017-0-01189-8Varga M., Grundtner R., Maj M., et al. Impact-abrasive wear resistance of high alumina ceramics and ZTA / Wear. 2023. Vol. 522. 204700. DOI: 10.1016/j.wear.2023.204700Varga M., Grundtner R., Maj M., et al. Impact-abrasive wear resistance of high alumina ceramics and ZTA / Wear. 2023. Vol. 522. 204700. DOI: 10.1016/j.wear.2023.204700Krell A., Klaffke D. Effect of grain size and humidity on fretting wear in fine-grained alumina, Al2O3/TiC, and zirconia / J. Am. Ceram. Soc. 1996. Vol. 79. No. 5. P. 1139 – 1146. DOI: 10.1002/chin.199640002Krell A., Klaffke D. Effect of grain size and humidity on fretting wear in fine-grained alumina, Al2O3/TiC, and zirconia / J. Am. Ceram. Soc. 1996. Vol. 79. No. 5. P. 1139 – 1146. DOI: 10.1002/chin.199640002Garshin A. P., Gropyanov V. M., Zaitsev G. P., Semenov S. S. Ceramics for mechanical engineering. — Moscow: Nauchtekhlitizdat, 2003. — 384 p. [in Russian].Garshin A. P., Gropyanov V. M., Zaitsev G. P., Semenov S. S. Ceramics for mechanical engineering. — Moscow: Nauchtekhlitizdat, 2003. — 384 p. [in Russian].Krell A., Blank P. The influence of shaping method on the grain size dependence of strength in dense submicrometre alumina / J. Eur. Ceram. Soc. 1996. Vol. 16. P. 1189 – 1200. DOI: 10.1016/0955-2219(96)00044-1Krell A., Blank P. The influence of shaping method on the grain size dependence of strength in dense submicrometre alumina / J. Eur. Ceram. Soc. 1996. Vol. 16. P. 1189 – 1200. DOI: 10.1016/0955-2219(96)00044-1Krell A. Improved hardness and hierarchic influences on wear in submicron sintered alumina / Mater. Sci. Eng. 1996. A209. P. 156 – 163. DOI: 10.1016/0921-5093(95)10155-1Krell A. Improved hardness and hierarchic influences on wear in submicron sintered alumina / Mater. Sci. Eng. 1996. A209. P. 156 – 163. DOI: 10.1016/0921-5093(95)10155-1Krell A. Fracture origin and strength in advanced pressureless-sintered alumina / J. Am. Ceram. Soc. 1998. Vol. 81.. No. 7. P. 1900 – 1906. DOI: 10.1111/j.1151-2916.1998.tb02564.xKrell A. Fracture origin and strength in advanced pressureless-sintered alumina / J. Am. Ceram. Soc. 1998. Vol. 81.. No. 7. P. 1900 – 1906. DOI: 10.1111/j.1151-2916.1998.tb02564.xWu Z., Chen J., Miao Z., et al. Brittleness reduction of Al2O3-C refractories: microstructure evolution and role of carbon fibers / Ceram. Int. 2024. Vol. 50. No. 18. P. 32163 – 32170. DOI: 10.1016/j.ceramint.2024.06.023Wu Z., Chen J., Miao Z., et al. Brittleness reduction of Al2O3-C refractories: microstructure evolution and role of carbon fibers / Ceram. Int. 2024. Vol. 50. No. 18. P. 32163 – 32170. DOI: 10.1016/j.ceramint.2024.06.023Krell A. Alumina structure with improved fracture properties / Phys. Status Solid. A. 1981. Vol. 63. P. 183 – 192. DOI: 10.1002/pssa.2210630125Krell A. Alumina structure with improved fracture properties / Phys. Status Solid. A. 1981. Vol. 63. P. 183 – 192. DOI: 10.1002/pssa.2210630125Vekinis G., Ashby M., Beaumont P. R-curve behaviour of Al2O3 ceramics / Acta Metallurg. Mater. 1990. Vol. 38. No. 6. P. 1151 – 1162. DOI: 10.1016/0956-7151(90)90188-mVekinis G., Ashby M., Beaumont P. R-curve behaviour of Al2O3 ceramics / Acta Metallurg. Mater. 1990. Vol. 38. No. 6. P. 1151 – 1162. DOI: 10.1016/0956-7151(90)90188-mOvidko I. A., Sheinerman A. G. Plastic deformation and fracture processes in metallic and ceramic nanomaterials with bimodal structures / Rev. Adv. Mater. Sci. 2007. Vol. 16. P. 1 – 9.Ovidko I. A., Sheinerman A. G. Plastic deformation and fracture processes in metallic and ceramic nanomaterials with bimodal structures / Rev. Adv. Mater. Sci. 2007. Vol. 16. P. 1 – 9.Pozdova T. S., Permin D. A., Nazmutdinov M. D., et al. Effect of precipitation acidity on the structure and morphology of α-Al2O3 powder particles / Inorg. Mater. 2024. Vol. 60. No. 10. P. 1197 – 1204. DOI: 10.1134/s0020168524701590Pozdova T. S., Permin D. A., Nazmutdinov M. D., et al. Effect of precipitation acidity on the structure and morphology of α-Al2O3 powder particles / Inorg. Mater. 2024. Vol. 60. No. 10. P. 1197 – 1204. DOI: 10.1134/s0020168524701590Borger A., Supancic P., Danzer R. The ball on three balls test for strength testing of brittle discs: stress distribution in the disc / J. Eur. Ceram. Soc. 2002. Vol. 22. P. 1425 – 1436. DOI: 10.1016/s0955-2219(01)00458-7Borger A., Supancic P., Danzer R. The ball on three balls test for strength testing of brittle discs: stress distribution in the disc / J. Eur. Ceram. Soc. 2002. Vol. 22. P. 1425 – 1436. DOI: 10.1016/s0955-2219(01)00458-7Borger A., Supancic P., Danzer R. The ball on three balls test for strength testing of brittle discs. Part II. Analysis of possible errors in the strength determination / J. Eur. Ceram. Soc. 2004. Vol. 24. P. 2917 – 2928. DOI: 10.1016/j.jeurceramsoc.2003.10.035Borger A., Supancic P., Danzer R. The ball on three balls test for strength testing of brittle discs. Part II. Analysis of possible errors in the strength determination / J. Eur. Ceram. Soc. 2004. Vol. 24. P. 2917 – 2928. DOI: 10.1016/j.jeurceramsoc.2003.10.035Fett T., Rizzi G., Ernst E., et al. A 3-balls-on-3-balls strength test for ceramic disks / J. Eur. Ceram. Soc. 2007. Vol. 27. P. 1 – 12. DOI: 10.1016/j.jeurceramsoc.2006.02.033Fett T., Rizzi G., Ernst E., et al. A 3-balls-on-3-balls strength test for ceramic disks / J. Eur. Ceram. Soc. 2007. Vol. 27. P. 1 – 12. DOI: 10.1016/j.jeurceramsoc.2006.02.033Liu C., Herzog S., Deng Y. Influence of laser surface texturing on the flexural strength of Al2O3 and Si3N4 / J. Eur. Ceram. Soc. 2022. Vol. 42. P. 4286 – 4295. DOI: 10.1016/j.jeurceramsoc.2022.04.013Liu C., Herzog S., Deng Y. Influence of laser surface texturing on the flexural strength of Al2O3 and Si3N4 / J. Eur. Ceram. Soc. 2022. Vol. 42. P. 4286 – 4295. DOI: 10.1016/j.jeurceramsoc.2022.04.013Michalek M., Michalkova M., Blugan G., Kuebler J. Strength of pure alumina ceramics above 1 GPa / Ceram. Int. 2018. Vol. 44. No. 3. P. 3255 – 3260. DOI: 10.1016/j.ceramint.2017.11.098Michalek M., Michalkova M., Blugan G., Kuebler J. Strength of pure alumina ceramics above 1 GPa / Ceram. Int. 2018. Vol. 44. No. 3. P. 3255 – 3260. DOI: 10.1016/j.ceramint.2017.11.098Goltsev V. Yu., Grigorev E. G., Osintsev A. V., et al. Analysis of the methods for bending small-sized disks on a ring support / Industr. Lab. Mater. Diagn. 2022. Vol. 88. No. 11. P. 66 – 72 [in Russian]. DOI: 10.26896/1028-6861-2022-88-ll-66-72Goltsev V. Yu., Grigorev E. G., Osintsev A. V., et al. Analysis of the methods for bending small-sized disks on a ring support / Industr. Lab. Mater. Diagn. 2022. Vol. 88. No. 11. P. 66 – 72 [in Russian]. DOI: 10.26896/1028-6861-2022-88-ll-66-72Popov A. A., Berendeev N. N., Boldin M. S., et al. New method of the estimation of the bending strength of ultrafine-grained structural ceramics for application in the conditions of multiaxial stress-strain state / J. Phys. Conf. Ser. 2020. Vol. 1431. P. 012031. DOI: 10.1088/1742-6596/1431/1/012031Popov A. A., Berendeev N. N., Boldin M. S., et al. New method of the estimation of the bending strength of ultrafine-grained structural ceramics for application in the conditions of multiaxial stress-strain state / J. Phys. Conf. Ser. 2020. Vol. 1431. P. 012031. DOI: 10.1088/1742-6596/1431/1/012031Ashby M. F., Jones D. R. H., David R. H. Engineering Materials. — Oxford: Butterworth-Heinemann, 2019. — 560 p. DOI: 10.1016/c2015-0-04446-xAshby M. F., Jones D. R. H., David R. H. Engineering Materials. — Oxford: Butterworth-Heinemann, 2019. — 560 p. DOI: 10.1016/c2015-0-04446-xKrell A., Kreher W. On subcritical crack growth in ceramics as influenced by grain size and energy-dissipative mechanisms / J. Mater. Sci. 1983. Vol. 18. P. 2311 – 2318. DOI: 10.1007/bf00541835Krell A., Kreher W. On subcritical crack growth in ceramics as influenced by grain size and energy-dissipative mechanisms / J. Mater. Sci. 1983. Vol. 18. P. 2311 – 2318. DOI: 10.1007/bf00541835Krell A., Blank P. Inherent reinforcement of ceramic microstructures by grain boundary engineering / J. Eur. Ceram. Soc. 1992. Vol. 9. P. 309 – 322. DOI: 10.1016/0955-2219(92)90066-mKrell A., Blank P. Inherent reinforcement of ceramic microstructures by grain boundary engineering / J. Eur. Ceram. Soc. 1992. Vol. 9. P. 309 – 322. DOI: 10.1016/0955-2219(92)90066-mOkuma G., Osada T., Minagawa H., et al. Heterogeneities and defects in powder compacts and sintered alumina bodies visualized by using the synchrotron X-ray CT / J. Eur. Ceram. Soc. 2023. Vol. 43. P. 486 – 492. DOI: 10.1016/j.jeurceramsoc.2022.10.020Okuma G., Osada T., Minagawa H., et al. Heterogeneities and defects in powder compacts and sintered alumina bodies visualized by using the synchrotron X-ray CT / J. Eur. Ceram. Soc. 2023. Vol. 43. P. 486 – 492. DOI: 10.1016/j.jeurceramsoc.2022.10.020Babichev A. P., Babushkina N. A., Bratovskiy A. M. Physical quantities. — Moscow: Energoatomitizdat, 1991. — 1232 p. [in Russian].Babichev A. P., Babushkina N. A., Bratovskiy A. M. Physical quantities. — Moscow: Energoatomitizdat, 1991. — 1232 p. [in Russian].

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