COLOUR CHARACTERISTICS OF DENSIFIED AND THERMALLY POST-TREATED BEECH AND PINE WOODS

Year 2016, Volume: 2 Issue: 2, 187 - 192, 19.12.2016

Hüseyin Pelit

https://doi.org/10.22531/muglajsci.283644

Cited By: 1

Abstract

Effect of thermo-mechanical densification and thermal post-treatment on the colour parameters (L*, a*, b* and ΔE*) of beech (Fagus oriantalis L.) and pine (Pinus sylvestris L.) wood species were investigated. Wood specimens were densified at temperatures of 100 or 150 °C and compression ratios of 20% or 40%. Then, thermal post-treatment was applied to the specimens during 2 h at 190, 200, and 210 °C to provide dimensional stability in densified specimens. The colour change of the specimens was evaluated by CIEL*a*b* colour co-ordinate systems. The results showed that, the colour of the densified specimens at higher temperature and compression ratio was more changed. The compression temperature was more effective compared to compression ratio on the colour change of specimens. After the thermal post-treatment, colour characteristics of specimens have changed significantly depending on the increase in the treatment temperature, and specimens darkened. Densification processes has little effect on colour changes of the thermally post-treated specimens. The colour of pine specimens compared with the beech specimens more affected by the densification and thermal treatment applications. Morever, the change in a* value of specimens is more evident than the change in L* or b* values.

Keywords

Wood material, Densification, Thermal treatment, Colour change

YOĞUNLAŞTIRILMIŞ VE TERMAL İŞLEMLİ KAYIN VE ÇAM ODUNLARININ RENK ÖZELLİKLERİ

Abstract

Kayın (Fagus oriantalis L.) ve çam (Pinus
sylvestris L.) odunu örneklerinin renk özellikleri (L*, a*, b* and ΔE) üzerine termo-mekanik
yoğunlaştırma ve termal işlemin etkisi araştırılmıştır. Örnekler 100 °C ve 150
°C sıcaklıkta %20 ve %40 sıkıştırma oranı ile yoğunlaştırılmıştır. Daha sonra,
yoğunlaştırılmış örneklerde boyutsal stabiliteyi sağlamak için 190, 200 ve 210
°C sıcaklıkta 2 saat süresince örneklere termal işlem uygulanmıştır. Örneklerin
renk değişimi CIEL*a*b* renk ko-ordinat sistemine göre değerlendirilmiştir. Araştırma
sonuçlarına göre, daha yüksek sıcaklıkta ve sıkıştırma oranında
yoğunlaştırılmış örneklerin rengi daha fazla değişmiştir. Örneklerin renk
değişiminde, sıkıştırma oranına göre sıkıştırma sıcaklığı daha çok etkilidir.
Termal işlem sonrası, örneklerin renk özellikleri işlem sıcaklığındaki artışa
bağlı olarak önemli ölçüde değişmiştir ve örnekler kararmıştır. Termal işlemli
örneklerdeki renk değişmelerinde yoğunlaştırma işlemlerinin etkisi önemsiz
bulunmuştur. Kayın örneklere göre çam örneklerin
rengi yoğunlaştırma ve termal işlem uygulamalarından daha fazla etkilenmiştir.
Ayrıca, örneklerin a* değerindeki değişim L* veya b* değerindeki değişimden
daha belirgindir.

Keywords

Ağaç malzeme, Yoğunlaştırma, Termal işlem, Renk değişimi

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