Journal of Science  and Technology of Composites

Journal of Science and Technology of Composites

Investigating the Effects of Skin Veneer and Core Density on the Physical and Mechanical Properties of Wooden Sandwich Panels

Document Type : Research Paper

Authors
Department of Wood Industry Engineering, The faculty of Civil Engineering, Shahid Rajaee Teacher Training University, Tehran, Iran.
10.22068/jstc.2026.2079813.1944
Abstract
Sandwich panels, as lightweight and strong structures, hold particular importance in the wood and construction industries. As the use of decorative veneers on these panels increases, evaluating their impact on physical and mechanical properties is essential. Furthermore, utilizing polymer foams as cores in these panels can mitigate the demand for raw wood materials, contributing to forest conservation and environmental sustainability. Therefore, this study aimed to investigate the effects of skin veneer and core density on the physical and mechanical properties of wooden sandwich panels. The panels were fabricated using 3 mm thick fiberboard (natural beech veneer, synthetic melamine veneer, and without veneer) as skin, expanded polystyrene (EPS) foam (densities of 8, 12, and 20 kg/m3) as the core, and polyvinyl acetate (PVA) as the adhesive. After making the samples by hot pressing, they were tested for bending strength, compressive strength, impact resistance, modulus of elasticity, and water absorption after 2 and 24 hours of immersion. The results indicated that the highest bending strength, modulus of elasticity, compressive strength, and impact resistance (2.363 MPa, 77.867 MPa, 0.056 MPa, and 72.667 kJ/m2, respectively) were achieved in sandwich panels featuring skin including beech veneer and a polystyrene core with a density of 20 kg/m3. The results indicate that the veneer type can influence some physical and mechanical properties of the made sandwich panels. Moreover, increasing the core density of core polystyrene led to improved mechanical strength and reduced water absorption in panels.
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