Bulletin of Forestry Science / Volume 10 / Issue 1 / Pages 17-27
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Changes in the heat conducting properties of wood materials as a result of thermal treatment

Zoltán Börcsök & Zoltán Pásztory


Correspondence: Börcsök Zoltán

Postal address: H-9400 Sopron, Bajcsy-Zs. u. 4.

e-mail: borcsok.zoltan[at]uni-sopron.hu


The aim of the research is to detect correlations between the heat treatment of wood at different durations and some of its physical properties and thermal conductivity. During the experiments, spruce (Picea abies), Pannonia poplar (Populus × euramericana cv. Pannonia) and rubber wood (Hevea brasiliensis) were subjected to heat treatment at 180°C for 15, 25 and 35 hours. Measurements confirmed that the equilibrium moisture content, the density and the thermal conductivity of the specimens made of heat-treated material were lower than those of the untreated specimens. The average equilibrium moisture content decreased from an initial value of around 12% to around 6% during the treatments in case of all three tree species. The decrease in density after 15, 25 and 35 hours of treatment was 9.1, 12.1 and 13.4% for poplar, 5.2, 7.6 and 8.7% for spruce and 3.5, 5.1% and 7.1% for rubber wood, respectively. The decrease in density after 15, 25 and 35 hours of treatment was 17.0, 24.2, 25.2% for poplar, 8.5, 11.6, 19.2% for spruce and 3.6, 4.1, and 8.0% for rubber wood, respectively. Literature data supports that heat treatment decreases the equilibrium wood moisture and density of the wood which explains the lower thermal conductivity compared to the control sample made from the same raw material.

Keywords: thermal treatment, wood, thermal conductivity, density, equilibrium moisture content

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    Cite this article as:

    Börcsök, Z. & Pásztory, Z. (2020): Changes in the heat conducting properties of wood materials as a result of thermal treatment. Bulletin of Forestry Science, 10(1): 17-27. (in Hungarian) DOI: 10.17164/EK.2020.002

    Volume 10, Issue 1
    Pages: 17-27

    DOI: 10.17164/EK.2020.002

    First published:
    11 May 2020

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