Physikalische Eigenschaften heimischer Holzarten nach Wärmebehandlung

2002

S. 111-113

16 Lit. Ang.

Unselbständiges Werk

200095826

Demand for ecologically compatible as well as hazard-free wood has been a high priority. Increased expectations have put thermal-treatment forward as a method of choice and alterations taking place in the wood need to be evaluated for individual species. This work presents wood physical properties of birch, beech, oak, ash, spruce and pine wood, each of them thermally-treated under varying temperatures and durations. Results confirm that improved dimension stability goes hand in hand with reductions in wood mass and mechanical strength, respectively. In contrast to others the ring-porous species oak and ash did show the same level of improvements already at lower temperatures (185 °C). Overall, with an average mass loss of 15% the equilibrium moisture content was reduced by 40-70% and the anti-swelling effciency was up by 30-60%. Bending strength was clearly lowered at all temperature levels. Experience has also revealed that process parameters need to be turned for each species separately, which is of particular importance during the initial drying phase.