2. |
- Rademacher, Peter, et al.
(författare)
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European co-operation in wood research From native wood to engineered materials : Part 3: engineered hybrid wood-based products
- 2017
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Ingår i: Pro Ligno. - Romania : Pro Ligno Foundation. - 1841-4737 .- 2069-7430. ; 13:4, s. 361-372
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Tidskriftsartikel (refereegranskat)abstract
- Forest-based industries have been continuously developing advanced processes, materials and wood-based solutions, to meet evolving demands and increase competitiveness. Engineered wood products (EWPs) constitute one emerging group of materials aiming at improved property profiles of wood, and provide desired shapes and functionality. In this paper, the main principles for different processes to soften wood and make it more flexible for bending and moulding, such as longitudinal compression, plasticization by water vapour and gaseous ammonia, and a dielectric heating technique, are discussed. Examples of implementation of these techniques for the production of wooden products are presented, and the use of reed canary grass, and a novel technique for embossment of hybrid particleboards are also further discussed.
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3. |
- Báder, Mátyás, et al.
(författare)
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Wood densification processing for newly engineered materials
- 2018
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Ingår i: Proceedings of the 5th International Conference on Processing Technologies for the Forest and Bio-based Products Industries (PTF BPI 2018), Freising/Münich, September 20-21. - Kuchl. ; , s. 255-263
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Konferensbidrag (refereegranskat)abstract
- Wood is a renewable, bio-based material with a mixture of different properties and qualities, used in numerous applications. Beside many species with high wood qualities several species suffer due to a number of disadvantages, where low hardness and abrasive resistance are characteristic for low-density species. This paper presents examples of on-going European research projects and industrial processes mostly related to wood densification methods. Wood densification is a classical thermohydro-mechanical (THM) wood treatment process, through which density is increased by mechanical compression of wood perpendicular to the grain, by impregnation of cell lumens or cell walls with solutions or melted substances (resins, waxes), or by a combination of both. The purpose is to produce newly designed and engineered materials and products with new property profiles, which would potentially find new markets. In general, the THM processes consist of three stages: plasticization of the wood cells, followed by the actualcompression, and finally solidification of the compressed wood in order to prevent elastic spring-back and the moisture-induced set-recovery. The wood densification process refers but is not limited to solid wood and might apply to whole wood pieces, or to local areas within given pieces only. Another THM method is the mechanical compression of wood parallel to the grain, which leads to a product with high flexibility. A European wood research network, represented by the authors of this contribution, has extended experience in many wood modification processes, as demonstrated through ongoing researches and case studies in this paper
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