Eğilmeye maruz bırakılmış PVC köpük çekirdekli sandviç levhaların deneysel ve sayısal analizi

Öz

Bu çalışmada, eğilmeye maruz bırakılan PVC köpük çekirdek ve kontrplak/MDF yüzeyler kullanılarak oluşturulan sandviç levhalar, deneysel ve sayısal yöntemler kullanılarak analiz edilmiştir. Sandviç levhalarda çekirdek olarak 60 kg/m3 yoğunlukta PVC köpük, yüzey malzemeleri olarak kayın kontrplak ve MDF kullanılmıştır. Sandviç katmanları çift bileşenli epoksi yapıştırıcı kullanılarak yapıştırılmıştır. Çalışmada kullanılan kontrplak ve MDF malzemelerin eğilme özellikleri belirlenerek sayısal modellemede kullanılmıştır. PVC köpük için üretici tarafından belirtilen elastikiyet değeri kullanılmıştır. Çalışmanın sonuçları, yüzey malzeme türünün PVC köpük çekirdekli sandviç levhaların eğilme davranışını önemli ölçüde etkilediğini göstermiştir. Kontrplak yüzeyler kullanıldığında, PVC köpük çekirdekli sandviç levhaların eğilmeye rijitliğinin ve dayanımının daha yüksek olduğu bulunmuştur. Test edilen sandviç levhalarda, baskın arıza türü yüzey malzemesinin kırılmasıdır. MDF yüzeylerde üst yüzeyde kırışma ve MDF/çekirdek kırılması gözlemlenmiştir. Çalışmanın sonuçları, sayısal modellerin, malzemelerin akma gerilmesi ve teğet modülü (plastik bölge) kullanılarak sandviç levhaların kırılmaya kadar olan eğilme davranışını doğru bir şekilde tahmin etmek için kullanılabileceğini göstermektedir.

Anahtar Kelimeler

• MDF
• Kontrplak
• PVC köpük sandviç
• Sonlu Eleman Analizi

Experimental and numerical analysis of PVC foam core sandwich panels subjected to bending

Öz

In this study, sandwich panels created using PVC foam core and plywood/ MDF surfaces subjected to bending were analyzed using experimental and numerical methods. The sandwich panels used PVC foam with a density of 60 kg/m³ as the core and beech plywood and MDF as the surface materials. The sandwich layers were bonded using a two-component epoxy adhesive. The bending properties of the plywood and MDF materials used in the study were determined and used in numerical modeling. The manufacturer's specified E value was used for the PVC foam. The results of the study showed that the type of surface material significantly affects the bending behavior of PVC foam core sandwich panels When plywood surfaces are used, PVC foam core sandwich panels have been found to have higher bending rigidity and strength. In the tested sandwich panels, the dominant failure type was fracture of the surface material. In MDF surfaces, wrinkling on the top surface and MDF/core fracture were observed. The results of the study demonstrate that numerical models can be used to accurately predict the bending behavior of sandwich panels up to fracture using the yield stress and tangent modulus (plastic region) of the materials.

Anahtar Kelimeler

• MDF
• Plywood
• PVC foam sandwich
• Finite Element Analysis

Kaynakça

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