1. UNIVERSITYFREIBURG IUFRO Division 5 Conference 5.04.06 – Wood drying Improving the dimensional stability of different wood species by thermal modification Denny OHNESORGE Corbat Holding SA, Swiss Wood Treatment Technology, Denmark University of Freiburg, Institute of Forest Utilization and Work Science, Germany

2. INSTITUTE of FOREST UTILIZATION and WORK SCIENCE 1 UNIVERSITYFREIBURG Authors/Institution Denny OHNESORGE*, Claudia STOLERU and Gero BECKER Albert-Ludwig-University Freiburg Institute of Forest Utilization and Work Science Werthmannstr. 6 D-79085 Freiburg, Germany E-mail:denny.ohnesorge@fobawi.uni-freiburg.de Web:http://www.forst.uni-freiburg.de/fobawi Improving the dimensional stability of different wood species by thermal modification

3. INSTITUTE of FOREST UTILIZATION and WORK SCIENCE 2 UNIVERSITYFREIBURG Objectives and Method  Improvement of wood properties by thermal modification with the aim to develop products for new usages  Moisture-Heat-Pressure-Treatment between 160 and 220°C with Treatment in a Vaccum kiln dryer samples Boards from 4 different wood species Poster presented results of: Sorbtion ability and Swelling & shrinking Several tests on hardness and strength Climate chamber

4. INSTITUTE of FOREST UTILIZATION and WORK SCIENCE 3 UNIVERSITYFREIBURG Results  Decrease of oven-dry density  Decrease of Sorbtion ability  Increase of dimensional stability (ASE-Index) Sorbtion abilitydimensional stability (ASE-Index)

5. INSTITUTE of FOREST UTILIZATION and WORK SCIENCE 4 UNIVERSITYFREIBURG Conclusions  Use of thermal modified, indigenous wood species in (for this wood species) new utilizations by improvement of: Natural durability Dimensional stability Terracce flooringsBathroom flooringsSolid furniture