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ŠUMARSKI LIST 9-10/2019 str. 50     <-- 50 -->        PDF

The density of thermally modified beech wood and hornbeam wood was about 10% lower than density of untreated wood.
Brinell hardness of thermally modified beech wood decreased for 3%, 15%, and 25% on cross, radial, and tangential section, respectively.
Brinell hardness of thermally modified hornbeam wood decreased for 6%, 18%, and 13% on cross, radial, and tangential section, respectively.
Mann-Whitney’s test found that all differences in Brinell hardness between thermally modified and unmodified wood were significant.
From these results, it is apparent that thermal modification adversely affects the wood hardness on all three sections in beech wood and hornbeam wood, although the wood hardness for the nonbearing wood structures and wood flooring is satisfactory.
The thermal modification processes of wood are still being investigated. Although thermally modified wood exhibits advantages in terms of aesthetic properties such as uniformity and change of color in darker tones and some technical properties, such as increased dimensional stability and improved resistance to decaying fungus, one should be aware of its drawbacks as compared to unmodified wood. It is necessary to develop the experience of the impact of thermal modification on each type of wood individually, as it has been shown that their properties change differently.
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