ISIL İŞLEMİN KAYIN ODUNUN MEKANİK ÖZELLİKLERİ VE BOYUTSAL KARARLILIĞI ÜZERİNE ETKİSİ

Öz

Farklı sıcaklıklarda özellikle yüksek sıcaklıklardaki termal modifikasyon odunun kimyasal, fiziksel ve mekanik özelliklerini değiştirmede etkili bir metottur. Bu çalışmada, ThermoWood metoduyla 170, 180, 190, ve 212 oC sıcaklıkta 2 saat süre ile ısıl işlem görmüş kayın odununun bazı mekanik ve fiziksel özellikleri araştırılmıştır. Sonuçlar tam kuru referans örnekler ile karşılaştırılmıştır. Sonuç olarak, ısıl işlem sıcaklığının artmasına bağlı olarak, eğilme direnci azalırken, liflere paralel basınç direnci ve elastikiyet modülü artmıştır. Ayrıca, işlem sıcaklığı yükseldikçe, denge rutubet miktarı azalmıştır. Boyutsal stabilizasyonda önemli ölçüde artış görülmüş ve bunun yanında odun örneklerinin rengi yeknesak bir şekilde koyulaşmıştır.

Anahtar Kelimeler

• Mekanik özellikler,Isıl işlem,Renk,Boyutsak kararlılık,Thermowood

EFFECT OF HEAT TREATMENT ON THE MECHANICAL PROPERTIES AND DIMENSIONAL STABILITY OF BEECH WOOD

Abstract

Thermal modification at different temperatures especially at high temperatures is an effective method to change chemical, physical, and mechanical properties of wood. In this study, some mechanical and physical properties of heat treated beech (Fagus orientalis) wood at temperatures 170, 180, 190, and 212^oC for 2 h with ThermoWood method were investigated. The results were compared with oven-dried reference samples. Consequently, depending on the increase of heat treatment temperature, the bending strength was decreasing, the compression strength parallel to the grain and modulus of elasticity increased. Also, when the treatment temperature increased, equilibrium moisture content decreased. It was seen that a significant increase of dimensional stability and besides the color of samples was darken uniformly.

Keywords

• Mechanical properties,Heat treatment,Color,Dimensional stability,Thermowood

Kaynakça

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