Sığ Kriyojenik İşlemin Sarıçam (Pinus sylvestris L.) Odunu Eğilme Direnci ve Elastikiyet Modülü Üzerine Etkilerinin Araştırılması

Abstract

Bu çalışmada farklı rutubet miktarına (RM) sahip (HK-Hava kurusu, LD- Lif doygunluğu ve SD- Suya doymuş) Sarıçam (Pinus sylvestris L.) odununa -70 oC’de sığ kriyojenik işlem (SKİ) uygulamanın ağaç malzemenin eğilme direnci ve elastikiyet modülü özelliklerindeki etkileri araştırılmıştır. Eğilme direncinin (ED) belirlenmesinde TS 2474, eğilmede elastikiyet modülünün (EEM) belirlenmesinde ise TS 2478 esaslarına uyulmuştur. SKİ uygulanması ile örneklerin ED ve EEM üzerinde kayda değer artışlar gözlenmiştir. Ayrıca SKİ uygulamanın ED ve EEM üzerindeki etkisi istatistiksel olarak anlamlı bulunmuştur (p≤0,05). Malzemelerin maruz kaldıkları RM arttıkça ED ve EEM değerlerinin düştüğü görülmüştür. RM’nin ED üzerindeki etkisi istatistiksel olarak anlamlı iken (p≤0,05), EEM üzerindeki etkisi anlamsız bulunmuştur. Çalışma sonucu en yüksek ED (101,16 N/mm2) - 70 oC SKİ uygulanmış HK rutubetindeki örneklerde görülürken en düşük ED (76,05 N/mm2) SKİ uygulanmamış SD örneklerde görülmüştür. Benzer şekilde en yüksek EEM (12629,2 N/mm2) SKİ uygulanmış HK rutubet miktarlı örneklere görülürken en düşük EEM (8759 N/mm2) SKİ uygulanmamış LD rutubet miktarına sahip örneklerde görülmüştür. Sonuç olarak SKİ uygulamanın ağaç malzemenin mekanik özellikleri üzerinde olumlu etkiye sahip olduğu söylenebilir.

Keywords

• Ağaç modifikasyonu
• Mekanik özellikler
• Sarıçam
• Sığ kriyojenik işlem

Investigation of the Effects of Shallow Cryogenic Treatment on Bending Strength and Modulus of Elasticity of Scots Pine (Pinus sylvestris L.)

Abstract

In this study, the application of shallow cryogenic treatment (SCT) to the Scotch Pine wood (Pinus sylvestris L.) which has different moisture content (MC type; AD-air dry, FS-fiber saturation and WS-water-saturated) and effects on bending strength and modulus of elasticity properties were investigated. TS 2474 principles were used for determination of bending strength (BS) and TS 2478 principles were used for determination of modulus of elasticity (MOE). Significant increases in the BS and MOE of the samples were observed with the application of SCT. In addition, the effect of SCT on BS and MOE was found to be statistically significant (p≤0.05). It was observed that BS and MOE values decreased due to the increase in MC to which the materials were exposed. The effect of MC on BS was statistically significant (p≤0.05) and there was no statistically significant difference for MOE. As a result of the study, the highest BS (101,16 N/mm2) was observed in AD moisture content samples with -70 oC SCT, while the lowest BS (76,05 N/mm2) was observed in WS moisture content samples without SCT. Similarly, the highest MOE (12629,2 N/mm2) was observed in AD moisture content samples with -70 oC SCT, while the lowest MOE (8759 N/mm2) was observed in FS moisture content samples without SCT. As a result, it could be said that SCT application has a positive effect on the mechanical properties of wood material.

Keywords

• Wood modification
• Mechanical properties
• Scotch Pine
• Shallow cryogenic treatment

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