Farklı yöntemlerle ısıl işlem uygulanmış ağaç malzemelerde yoğunluk ve eğilme direncinin belirlenmesi

Bu çalışmada, ağaç malzemelerin hava kurusu yoğunluk ve eğilme direnci üzerine farklı yöntem ve sıcaklık koşullarında uygulanan ısıl işlemlerin etkisi analiz edilmiştir. Sarıçam (Pinus silvestris L.) ve kayın (Fagus sylvatica L.) odunu örnekleri ThermoWood, yağlı işlem ve sıcak hava yöntemleri kullanılarak üç farklı sıcaklıkta (170 °C, 190 °C ve 210 °C) ayrı ayrı ısıl işleme tabi tutulmuştur. Deney örneklerinin yoğunluk ve eğilme direnci sırası ile TS 2472 ve TS 2474 esaslarına uyularak belirlenmiştir. Araştırma sonuçlarına göre, ısıl işlem yöntemi ve işlem sıcaklığındaki farklılaşma ahşap örneklerin yoğunluk ve eğilme direnci değerleri üzerinde önemli bulunmuştur. Isıl işlem yöntemi açısından, her iki ağaç türü için en yüksek yoğunluk ve eğilme direnci yağlı ısıl işlem görmüş örneklerde elde edilmiştir. Ayrıca, sıcak hava yöntemine göre ThermoWood yöntemi ile işlem görmüş örneklerde daha yüksek direnç değerleri bulunmuştur. Tüm yöntemler için, ısıl işlem sıcaklığındaki artışa bağlı olarak ahşap örneklerde yoğunluk ve eğilme direnci değerleri azalmıştır. Sıcaklık artışından kaynaklanan yoğunluk ve direnç kayıpları yağlı ısıl işlem yönteminde en az seviyede iken, sıcak hava yönteminde en fazla orana sahiptir.

Anahtar Kelimeler:

Ağaç malzeme, Eğilme direnci, Isıl işlem yöntemi, Yoğunluk

Determination of density and bending strength of heat-treated wood materials with different methods

In this study, the effect of heat treatments applied in different methods and temperature conditions on the air-dry density and bending strength of wood materials was analyzed. Scotch pine (Pinus silvestris L.) and beech (Fagus sylvatica L.) wood samples were heat treated separately at three different temperatures (170 °C, 190 °C and 210 °C) using ThermoWood, oil treatment and hot air methods. Density and bending strength of the test samples were determined in accordance with the principles of TS 2472 and TS 2474, respectively. According to the results of the study, the variation in heat treatment method and processing temperature was found to be significant on the density and bending strength values of the wood samples. In terms of heat treatment method, the highest density and bending strength for both wood species were obtained in oil heat-treated samples. In addition, higher strength values were found in the samples treated with the ThermoWood method compared to the hot air method. For all methods, the density and bending strength values of the wood samples decreased depending on the increase in the heat treatment temperature. Density and strength losses due to temperature increase were determined the lowest in the oil heat treatment method and the highest in the hot air method.

Keywords:

Wood materials, Bending strength, Heat treatment method, Density,

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Aydemir, D., Gündüz, G., Altuntaş, E., Ertas, M., Şahin, H. T., and Alma, M. H. 2011. Investigating changes in the chemical constituents and dimensional stability of heattreated hornbeam and Uludağ fir wood, BioResources 6(2), 1308-1321. https://doi.org/10.15376/biores.6.2.1308-1321
Aytin, A., Korkut, S., Ünsal, Ö., and Çakıcıer, N. 2015. The effects of heat Treatment with the ThermoWood method on the equilibrium moisture content and dimensional stability of wild cherry wood, BioResources 10(2), 2083-2093. https://doi.org/10.15376/biores.10.2.2083-2093
Bekhta, P., and Niemz, P. 2003. Effect of high temperature on the change in color, dimensional stability and mechanical properties of spruce wood, Holzforschung 57(5), 539-546. https://doi.org/10.1515/HF.2003.080
Boonstra, M. J., Rijsdijk, J. F., Sander, C., Kegel, E., Tjeerdsma, B., Militz, H., and Stevens, M. 2006. Microstructural and physical aspects of heat treated wood. Part 1. Softwoods, Maderas. Ciencia y Tecnología 8(3), 193-208. https://doi.org/10.4067/S0718- 221X2006000300006
Boonstra, M. J., Van Acker, J., Tjeerdsma, B. F., Kegel, E. V. 2007. Strength properties of thermally modified softwoods and its relation to polymeric structural wood constituents, Ann. For. Sci. 64(7), 679-690. https://link.springer.com/article/10.1051/forest:2007048
Boonstra, M. J. 2008. A Two-Stage Thermal Modification of Wood, Ph.D. Dissertation, Ghent University, Ghent, Belgium, and Université Henry Poincaré, Nancy, France. https://biblio.ugent.be/publication/468990
Bozkurt, A.Y., Göker, Y., Erdin, N. 1993. Emprenye Tekniği, İstanbul Üniversitesi Yayınları No: 3779/425.
Esteves, B. M., Pereira, H. M. 2009. Wood modification by heat treatment: A review. BioResources, 4(1), 370-404. https://doi.org/10.15376/biores.4.1.370-404
Finnish Thermowood Association, 2003. ThermoWood Handbook, FIN-00171, Helsinki, Finland.
González-Peña, M. M., Hale, M. D. 2009. Colour in thermally modified wood of beech, Norway spruce and Scots pine. Part 1: Colour evolution and colour changes. Holzforschung. https://doi.org/10.1515/HF.2009.078
Hill, C. A. S. 2006. Wood Modification: Chemical, Thermal and Other Processes, Wiley, Chichester, United Kingdom
Kamdem, D.P., Pizzi, A., Jermannaud, A., 2002. Durability of heat treated wood. Holz als Roh -und Werkstoff 60(1): 1-6. https://doi.org/10.1007/s00107-001-0261-1
Kaygın, B., Gündüz, G., Aydemir, D. 2009. Some physical properties of heattreated paulownia (Paulownia elongata) wood, Dry. Technol. 27(1), 89-93. https://doi.org/10.1080/07373930802565921
Kocaefe, D., Poncsak, S., Boluk, Y. 2008. Effect of thermal treatment on the chemical composition and mechanical properties of birch and aspen, BioResources 3(2), 517-537. https://doi.org/10.15376/biores.13.1.157-170
Kocaefe, D., Huang, X., Kocaefe, Y. 2015. Dimensional stabilization of wood, Curr. For. Rep. 1(3), 151-161. https://doi.org/10.1007/s40725-015-0017-5
Korkut, S., Kök, M. S., Korkut, D. S., Gürleyen, T. 2008. The effects of heat treatment on technological properties in red-bud maple (Acer trautvetteri Medw.) wood, Bioresource Technology, 99(6), 1538-1543. https://doi.org/10.1016/j.biortech.2007.04.021
Korkut, D. S., Guller, B. 2008. The effects of heat treatment on physical properties and surface roughness of red-bud maple (Acer trautvetteri Medw.) wood. Bioresource Technology, 99(8), 2846-2851. https://doi.org/10.1016/j.biortech.2007.06.043
Korkut, S., Kocaefe, D. 2009. Isıl işlemin odun özellikleri üzerine etkisi”, Düzce Üniversitesi Orman Fakültesi Ormancılık Dergisi, 5(2), 11–34.
Lekounougou, S., Kocaefe, D. 2014. Durability of thermally modified Pinus banksiana (Jack pine) wood against brown and white rot fungi, Int. Wood Prod. J. 5(2), 92-97. https://doi.org/10.1179/2042645313Y.0000000057
Mayes, D. and Oksanen, O. 2002. ThermoWood Handbook, Finnforest, Finland
Militz, H. 2005. Preface of the second European Conference on Wood Modification, in Proceedings for the 2nd European conference on wood modification, October 6-7 2005, Gottingen, Germany.
Pelit, H. 2014. Yoğunlaştırma ve ısıl işlemin doğu kayını ve sarıçamın bazı teknolojik özellikleriyle üstyüzey işlemlerine etkisi, Doktora tezi, Mobilya ve Dekorasyon Eğitimi, Gazi Üniversitesi, Ankara,Türkiye.
Pelit, H., Budakçı, M., Sönmez, A. 2016. Effects of heat post-treatment on dimensional stability and water absorption behaviours of mechanically densified Uludağ fir and black poplar woods. BioResources, 11(2), 3215-3229. https://doi.org/10.15376/biores.11.2.3215-3229
Pelit, H. 2017. The effect of different wood varnishes on surface color properties of heat treated wood materials. Journal of the Faculty of Forestry Istanbul University, 67(2), 262-274. https://doi.org/10.17099/jffiu.300010
Pelit, H., Budakçı, M., Sönmez, A. 2018. Density and some mechanical properties of densified and heat post-treated Uludağ fir, linden and black poplar woods. European Journal of Wood and Wood Products, 76(1), 79-87. https://doi.org/10.1007/s00107-017-1182-y
Pelit, H., Yorulmaz, R. 2019. Influence of densification on mechanical properties of thermally pretreated spruce and poplar wood. BioResources, 14(4), 9739-9754. https://doi.org/10.15376/biores.14.4.9739-9754
Percin, O., Peker, H., Atılgan, A. 2016. The effect of heat treatment on the some physical and mechanical properties of beech (Fagus orientalis lipsky) wood. Wood Research, 61(3), 443-456.
Rowell R. M. 2012. Handbook of wood chemistry and wood composites. CRC Press, Boca Raton. https://doi.org/10.1201/9780203492437
Sandberg, D., Haller, P., Navi, P. 2013. Thermo-hydro and thermo-hydromechanical wood processing: An opportunity for future environmentally friendly wood products, Wood Materials Science & Engineering 8(1), 64-88. https://doi.org/10.1080/17480272.2012.751935
Sandberg, D., Kutnar, A., Mantanis, G. 2017. Wood modification technologies-a review. iForest-Biogeosciences and Forestry, 10(6), 895-908. https://doi.org/10.3832/ifor2380-010
Sandberg, D., Kutnar, A., Karlsson, O., Jones, D. 2021. Wood Modification Technologies. Principles, Sustainability, and the Need for Innovation (Boca Raton: CRC Press), 432 pp. https://doi.org/10.1201/9781351028226
Sikora, A., Kačík, F., Gaff, M., Vondrová, V., Bubeníková, T., Kubovský, I. 2018. Impact of thermal modification on color and chemical changes of spruce and oak wood, J. Wood Sci. 64(4), 406-416. https://doi.org/10.1007/s10086-018-1721-0
Sivrikaya, H., Tesařová, D., Jeřábková, E., Can, A. 2019. Color change and emission of volatile organic compounds from Scots pine exposed to heat and vacuum-heat treatment. Journal of Building Engineering, 26, 100918. https://doi.org/10.1016/j.jobe.2019.100918
Tjeerdsma, B., Militz, H. 2005. Chemical changes in hydrothermal treated wood: FTIR analysis of combined hydrothermal and dry heat-treated wood, Holz als Rohund Werkst 63(2), 102-111. https://doi.org/10.1007/s00107-004-0532-8
Toker, H., Baysal, E., Kötekli, M., Türkoğlu, T., Kart, Ş., Şen, F., Peker, H. 2016. Surface characteristics of Oriental beech and Scots pine woods heat-treated above 200 °C, Wood Res. 61(1), 43-54.
Torniainen, P., Jones, D., Sandberg, D. 2021. Colour as a quality indicator for industrially manufactured ThermoWood. Wood Material Science & Engineering, 16:4, 287-289. https://doi.org/10.1080/17480272.2021.1958920
Tümen, İ., Aydemir, D., Gündüz, G., Üner, B., Çetin, H. 2010. Changes in the chemical structure of thermally treated wood, BioResources 5(3), 1936-1944. https://doi.org/10.15376/biores.5.3.1936-1944
TS 2470, 1976. Odunda Fiziksel ve Mekaniksel Deneyler İçin Numune Alma Metotları ve Genel Özellikler, T.S.E., Ankara.
TS 2471, 1976. Odunda, fiziksel ve mekaniksel deneyler için rutubet miktarı tayini, T.S.E., Ankara.
TS 2472, 1976. Odunda fiziksel ve mekanik deneyler için birim hacim ağırlığı tayini, T.S.E., Ankara.
TS 2474, 1976. Odunun statik eğilme dayanımının tayini, T.S.E., Ankara.
Yalçın, M., Şahin, H. İ. 2015. Changes in the chemical structure and decay resistance of heat-treated narrow-leaved ash wood, Maderas- Cienc. Tecnol. 17(2), 435-446. https://doi.org/10.4067/S0718-221X2015005000040
Yang, H., Yan, R., Chen, H., Lee, D. H., Zheng, C. 2007. Characteristics of hemicelluloses, cellulose and lignin pyrolysis, Fuel 86(12-13), 1781-1788. https://doi.org/10.1016/j.fuel.2006.12.013
Yıldız, S., Gezer, E. D., Yıdız, Ü. C. 2006. Mechanical and chemical behavior of spruce wood modified by heat, Build. Environ. 41(12), 1762-1766. https://doi.org/10.1016/j.buildenv.2005.07.017