mamad Mobilya ve Ahşap Malzeme Araştırmaları Dergisi 2636-8625 Bekir Cihad BAL 10.33725/mamad.1814696 Wood Based Composites Ahşap Esaslı Kompozitler Evaluation of some mechanical properties of poplar plywood reinforced with pine, beech and birch veneer Çam, kayın ve huş kaplama ile güçlendirilmiş kavak kontrplağın bazı mekanik özelliklerinin değerlendirilmesi https://orcid.org/0000-0002-3289-7831 Çavuş Vedat İZMİR KATİP ÇELEBİ ÜNİVERSİTESİ, ORMAN FAKÜLTESİ https://orcid.org/0000-0001-7097-4132 Bal Bekir Cihad KAHRAMANMARAŞ SÜTÇÜ İMAM ÜNİVERSİTESİ, TEKNİK BİLİMLER MESLEK YÜKSEKOKULU, MALZEME VE MALZEME İŞLEME TEKNOLOJİLERİ BÖLÜMÜ 12 26 2025 8 2 445 455 10 31 2025 12 03 2025 Copyright © 2018, Furniture and Wooden Material Research Journal 2018 Furniture and Wooden Material Research Journal

Plywood is the oldest known engineered wood material. While newer materials are being produced to replace plywood today, it is still widely used in some areas. Plywood is particularly used for concrete formwork and in applications requiring high strength. Therefore, the production of reinforced plywood has been the primary objective of some studies. This study aimed to strengthen poplar plywood, which has low mechanical performance, with relatively higher-performance veneer sheets. Selected properties of poplar plywood using pine, beech, and birch veneers as surface layers were investigated. The bending strength, flexural modulus of elasticity, Janka hardness, screw holding capacity, tensile-shear strength, and density of the produced plywood were determined. The data obtained indicated that the groups with birch and beech veneers in the surface layers generally exhibited higher mechanical performance. Compared to the control group, which used only poplar veneers, the bending strength of the group with birch veneers in the surface layers increased by approximately 50%. The increase in other mechanical properties was also approximately the same. When the results obtained are compared with some previous studies, it can be said that better results were obtained from the reinforcement studies carried out with glass fiber.

Kontrplak, bilinen en eski mühendislik ürünü ahşap esaslı bir malzemedir. Günümüzde, kontrplak yerine üretilen yeni malzemeler olsa da hala bazı alanlarda fazlaca kullanılmaktadır. Özellikle beton kalıbı olarak ve yüksek mukavemet aranan yerlerde kontrplak kullanılmaktadır. Bu bağlamda, kavak kontrplağın çeşitli ağaç kaplamalarla birlikte kullanılarak mekanik özelliklerinin iyileştirilmesi, bu çalışmanın temel amacı olmuştur. Bu çalışmada; düşük mekanik performansa sahip kavak kontrplağın, nispeten daha yüksek performansa sahip kaplama levhaları ile güçlendirilmesi amaçlanmıştır. Bu çalışmada, yüzey tabakalarında çam, kayın ve huş kaplama kullanılan kavak kontrplağın bazı seçili özellikleri araştırılmıştır. Üretilen kontrplakların eğilme direnci, eğilmede elastikiyet modülü, janka sertlik değeri, vida tutma kapasitesi, çekme-makaslama direnci ve yoğunluğu belirlenmiştir. Elde edilen verilere göre, yüzey tabakalarında huş ve kayın kaplama kullanılan grupların genel olarak mekanik performansının daha yüksek olduğu belirlenmiştir. Özellikle yalnızca kavak kaplamadan oluşan kontrol grubuna kıyasla, yüzeylerinde huş kaplama kullanılan grupta eğilme direncinin %62.71 oranında arttığı belirlenmiştir. Elde edilen diğer mekanik özelliklerde de artış oranı yaklaşık olarak bu seviyededir. Elde edilen sonuçlar, bazı önceki çalışmalarla kıyaslandığında, cam elyafla yapılan güçlendirme çalışmalarından daha iyi sonuçlar elde edildiği söylenebilir.

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