Mikrodalga İşlemi Görmüş ve Açık Hava Şartlarında Bekletilmiş Okaliptus (Eucalyptus camaldulensis Dehn) Odununun Yüzey Renk ve Pürüzlülük Özellikleri

Öz

Dış hava şartlarının, mikrodalga işlemi (MW) sonrası yüzey özelliklerini önemli ölçüde etkilediği gözlemlenmiştir. Renk parlaklık (L*), yeşil-kırmızılık (a*) ve sarı-mavilik (b*) renk koordinatlarının tümü önemli ölçüde değişmiştir. Bununla birlikte, en yüksek parlaklık azaltıcı değerler ΔL: -24.36 ve -25.79 (metrik) olarak, sırasıyla bir ve iki aylık hava koşullarına maruz kalmış numuneler için, 180 W ve 30 saniye koşullarında MW işlemi görmüş numunelerde gözlenmiştir. İki aylık hava koşullarına maruz kalma sürelerinin genellikle numunelerin daha açık tonların oluşmasına etkisi ilginçtir. Toplam renk farkı değerlerinin (ΔE) başlangıçta, düşük güç seviyelerinde (90 ve 180 W) arttığı, ardından MW işlem koşullarının daha yüksek güç seviyelerinde (360 ve 600 W) uygulanmasıyla azalma eğiliminde olduğu görülmüştür. Ayrıca, kroma ölçümleriyle odun numunelerinin renk doygunluk özelliklerinin değiştiği anlaşılmıştır. MW işlemleri, liflere her iki yönde de, (paralel ve dik) yüzey pürüzlülüğü değerlerinde artış sağladığı görülmüştür. Bu çalışmada bulunan sonuçlar, literatürde bildirilen ısıl işlemler ve dış hava koşulalarda elde edilen bulguların yüzey renk ve pürüzsüzlük özelliklerine etkileri sonuçlarıyla uyum içinde olduğu gözlemlenmiştir.

Anahtar Kelimeler

• Okoliptus odunu
• yüzey pürüzlülüğü
• renk özellikleri
• mikrodalga işlemi
• CIE L*a*b*
• Sarıçam odunu

Effects on Surface Color and Roughness Properties of Post-Microwave Treated Eucalyptus (Eucalyptus camaldulensis Dehn) Wood

Öz

It has been observed that weathering significantly influenced the Microwave (MW) post-treated samples. All color coordinates of Lightness (L*), red-green (a*), and yellow-blue (b*) color coordinates changed significantly. However, the highest lightness-reducing values of ΔL: -24.36 and -25.79 (metric) were observed in MW-treated samples at 180 W and 30 s. conditions for one and two-month weathered samples, respectively. It is interesting to note that two months of weathering usually impact the lighter tone of samples. Total color difference values (ΔE) appeared to increase initially at lower power levels (90 and 180 W), then decrease at higher power levels (360 and 600 W) of MW treatment conditions. It is also further evidenced by the discoloration of wood samples with chroma measurements. The MW treatments have also had an impact on increasing the trend toward higher surface roughness values in MW-treated samples under all conditions, in both directions (parallel to and perpendicular to the grain). It is also realized that post-MW treated and weathered samples show a smooth trend, with no clear effects observed under varying MW treatment conditions (power and time). The measured results found in this study are in good agreement with the results reported in the literature which indicate that heat treatments and weathering affect surface color and smoothness properties.

Anahtar Kelimeler

• Eucalyptus wood
• surface roughness
• color properties
• Microwave treatment
• CIE L*a*b*
• Scots pine wood

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