Lesnoy Vestnik / Forestry BulletinLesnoy Vestnik / Forestry BulletinЛесной вестник / Forestry Bulletin2542-1468Eco-Vector71637110.17816/2542-1468-2026-4-110-121Wood processing and chemical processing of woodДеревообработка и химическая переработка древесиныResearch ArticleToughness index of three thermally modified hardwoodsОпределение показателей прочности термически модифицированной древесины трех лиственных породGorbachevaGalina A.ГорбачеваГалина Александровна
Russian Federation

Cand. Sci. (Tech.), Associate Professor

канд. техн. наук, доцент

gorbacheva@bmstu.ruSkuratovNikolay V.СкуратовНиколай Владимирович
Russian Federation

Cand. Sci. (Tech.), Associate Professor

канд. техн. наук, доцент

skuratov@bmstu.ruSobolevAndrey V.СоболевАндрей Викторович
Russian Federation

Cand. Sci. (Tech.), Associate Professor

канд. техн. наук, доцент

avsobolev@bmstu.ruUsovDmitry V.УсовДмитрий Владимирович
Russian Federation

PhD student

аспирант

usik82.82@mail.ruBMSTU (Mytishchi branch)ФГАОУ ВО «Московский государственный технический университет имени Н.Э. Баумана (национальный исследовательский университет)» (Мытищинский филиал)110720263041101211107202611072026Copyright ©; 2026, Gorbacheva G.A., Skuratov N.V., Sobolev A.V., Usov D.V.Copyright ©; 2026, Горбачева Г.А., Скуратов Н.В., Соболев А.В., Усов Д.В.2026Gorbacheva G.A., Skuratov N.V., Sobolev A.V., Usov D.V.Горбачева Г.А., Скуратов Н.В., Соболев А.В., Усов Д.В.https://creativecommons.org/licenses/by/4.0https://journals.eco-vector.com/2542-1468/article/view/716371

The results of complex tests of the mechanical properties of birch, ash and oak wood subjected to intensive thermal treatment according to the Thermo D class are presented. The toughness indices were determined during tests in various structural directions for compression and static bending, as well as hardness and screw pull-out resistance. The values of the modulus of elasticity under static bending were obtained. All tests were carried out on small clear specimens of standard sizes. A comparative analysis of the established indicators of the mechanical properties of thermally modified birch, ash and oak wood with similar characteristics of native wood of the same species, taken from literary sources, was conducted. The ambiguity of the effect of intensive heat treatment on the considered mechanical properties and the modulus of elasticity under static bending of these wood species was revealed. It was found that there is a significant decrease in the strength of birch and oak wood under static bending after thermal treatment, while for ash wood such an effect could not be identified. It is shown that as a result of thermal modification, the static hardness of the radial and tangential surfaces of birch and ash samples decreases most significantly. A noticeable decrease in hardness of the radial surfaces of oak specimens was also noted, but at the same time, the hardness of their tangential surfaces changed insignificantly. It is indicated that thermal modification has a lesser effect on the strength of wood of all considered species under compression along and across the grain. It was established that as a result of thermal treatment, the wood of the studied species retained the ratios of anisotropy of mechanical properties with some modifications.

Приведены результаты комплексных испытаний механических свойств древесины березы, ясеня и дуба, подвергнутой интенсивной термической обработке по классу Thermo D. Определены показатели прочности при испытаниях в различных структурных направлениях на сжатие и статический изгиб, а также твердость и удельное сопротивление выдергиванию шурупов. Получены значения модуля упругости при статическом изгибе. Все проведенные испытания были выполнены на малых чистых образцах стандартных размеров. Проведен сравнительный анализ установленных показателей механических свойств термически модифицированной древесины березы, ясеня и дуба с аналогичными характеристиками нативной древесины тех же пород, взятыми из литературных источников. Выявлена неоднозначность влияния интенсивной термической обработки на рассматриваемые показатели механических свойств и модуля упругости при статическом изгибе указанных пород древесины. Установлено существенное снижение прочности древесины березы и дуба при статическом изгибе после проведения термической обработки, в то же время для древесины ясеня такое влияние выявить не удалось. Показано, что в результате термического модифицирования наиболее существенно снижается статическая твердость радиальных и тангенциальных поверхностей образцов березы и ясеня. Также отмечено заметное уменьшение твердости радиальных поверхностей образцов дуба, но при этом твердость их тангенциальных поверхностей изменилась незначительно. Указывается, что термическая модификация в меньшей мере влияет на прочность древесины всех рассматриваемых пород при сжатии вдоль и поперек волокон. Установлено, что в результате термической обработки древесина исследованных пород с некоторыми изменениями сохранила соотношения анизотропии механических свойств.

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