Investigation of Some Technological Properties of Three African Tropical Woods: Ayous, Iroko, Sapelli

Year 2025, Volume: 25 Issue: 2, 220 - 232, 30.09.2025

Elif Topaloğlu , Derya Ustaömer , Murat Ozturk

https://doi.org/10.17475/kastorman.1787607

Abstract

Aim of study: This study aim to investigate the anatomical features, density values, surface roughness, hardness and color parameters of three African tropical hardwood species: Ayous (Triplochiton scleroxylon K.Schum.), Iroko (Milicia excelsa (Welw.) C.C.Berg) and Sapelli (Entandrophragma cylindricum (Sprague) Sprague & Hoyle).
Material and method: Anatomical properties of tropical wood samples were determined by sectioning and preparation, and fiber characteristics were determined using the Schultze maceration method. Two density values were calculated for wood samples at 0% and 12% moisture content, namely oven dry and air dry, respectively. Surface roughness, hardness, and color were measured on radial and tangential surfaces.
Main results: All three tropical woods have diffuse-porous. Sapelli was found to have the greatest density values, while Ayous had the smallest. It was determined that both radial and tangential surfaces of Sapelli were harder compared to other species; and according to the average roughness value, the roughness values of both radial and tangential surfaces of Iroko were smaller than the roughness values of other species. The lightness value (L*), one of the color parameters, was found to be greatest for Ayous and smallest for Sapelli.
Research highlights: This study filled the gap in these research areas by determining especially the quantitative anatomical features in wood anatomy and surface features of Ayous, Iroko and Sapelli.

Keywords

African Tropical Woods , Anatomical Properties , Surface Properties , Wood Density

Thanks

The authors would like to thank Hasan Yılmaz for providing the wood samples.

Üç Tropikal Afrika Odununun Teknolojik Özelliklerinin Araştırılması: Ayous, Iroko, Sapelli

Abstract

Çalışmanın amacı: Bu çalışmanın amacı, Afrika'da yetişen üç tropikal sert ağaç türü olan Ayous (Triplochiton scleroxylon), Iroko (Milicia excelsa) ve Sapelli'nin (Entandrophragma cylindricum) anatomik özelliklerini, yoğunluk değerlerini, yüzey pürüzlülüğünü, sertliğini ve renk parametrelerini araştırmaktır.
Materyal ve yöntem: Kesit alma ve preparasyon işlemleri yapılarak tropikal odun örneklerinin anatomik özellikleri ve Schultze maserasyon metodu kullanarak lif karakteristikleri belirlenmiştir. Odun örneklerinin %0 ve %12 rutubet değerlerinde sırasıyla tam kuru ve hava kurusu olmak üzere iki yoğunluk değeri hesaplanmıştır. Radyal ve teğet yüzeylerde yüzey pürüzlülüğü, yüzey sertliği ve renk ölçümleri gerçekleştirilmiştir.
Temel sonuçlar: Her üç tropikal odun dağınık trahelidir. Sapelli'nin yoğunluk değerlerinin en büyük Ayous'un yoğunluk değerlerinin en küçük olduğu bulunmuştur. Sapelli'nin hem radyal hem de teğet yüzeylerinin diğer türlere kıyasla daha sert olduğu; ortalama pürüzlülük değerine göre Iroko'nun hem radyal hem de teğet yüzeylerinin pürüzlülük değerlerinin diğer türlerin pürüzlülük değerlerinden daha küçük olduğu belirlenmiştir. Renk parametrelerinden biri olan ışıklılık değeri (L*) Ayous için en büyük, Sapelli için en küçük bulunmuştur.
Araştırma vurguları: Bu çalışma, Ayous, Iroko ve Sapelli'nin özellikle odun anatomisi alanındaki sayısal anatomik özelliklerini ve yüzey özelliklerini belirleyerek bu araştırma alanlarındaki boşluğu doldurmuştur.

Keywords

Afrika Tropikal Odunları , Anatomik Özellikler , Yüzey Özellikleri , Odun Yoğunluğu

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