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

Abstract

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

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

Abstract

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.

Keywords

• Ağaç malzeme
• Eğilme direnci
• Isıl işlem yöntemi
• Yoğunluk

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