Alüminyum Yüzey Plakası / Genişletilmiş Polipropilen Köpük Çekirdekli Sandviç Levhaların Çarpışma Enerjisi Sönümleme ve Mukavemet Özelliklerinin Deneysel Olarak İncelenmesi

Öz

Son on yılda gelişen elektrikli araç endüstrisi nedeniyle araç gövdelerinde ağırlık azaltma çalışmaları büyük önem kazanmıştır. Köpük dolgulu sandviç yapılar, elektrikli bireysel ve toplu taşıma araçlarının gövdelerinde hem ağırlık azaltma hem de mukavemet koşulları sağlaması açısından en ideal malzemeler olarak öne çıkmaktadır. Bu çalışmada, alüminyum levhalar arasına iki farklı yoğunluktaki EPP köpükler yerleştirilmiş ve iki yapının EVA esaslı yapıştırıcı ile birleştirilmesiyle sandviç yapılar elde edilmiştir. Üretilen sandviç yapıların basma ve eğilme davranışları statik ve dinamik yükleme koşulları altında incelenmiştir. Yapılan testler ile sandviç yapıların dayanımları ve absorbe ettikleri enerji miktarları deneysel olarak hesaplanmış ve karşılaştırılmıştır. Elde edilen sonuçlara göre, tüm testlerde daha yoğun olan D2 köpüğünün, düşük yoğunluklu D1 köpüğüne göre yaklaşık 1.4 ila 2.05 kat daha fazla mukavemet sergilediği gözlemlenmiştir. D2 köpüğü absorbe ettiği enerji açısından diğer köpüğe göre 1,25 ila 2,5 kat daha fazla enerji sönümlemiştir. Bu durumun aksi bir davranış yapılan testlerde sadece dinamik basma testinde meydana gelmiştir. Sandviç yapıların hasar sonrası davranışı incelendiğinde, hasarın sonrasındaki 72 saat sonunda D2 köpüğün orijinal boyutuna çok benzer boyutlara geri döndüğü ve daha fazla deformasyonu geri verdiği gözlemlenmiştir.

Anahtar Kelimeler

• Sandviç Kompozit Yapılar
• Polipropilen Köpük
• Enerji Sönümleyici Yapılar
• Otomotiv Ağırlık Azaltma

EXPERIMENTAL INVESTIGATION OF CRUSH ENERGY ABSORPTION AND STRENGTH PROPERTIES OF SANDWICH PLATES WITH ALUMINUM FACESHEET/ EXPANDED POLYPROPYLENE FOAM CORE

Öz

Due to the developing electric vehicle industry in the last decade, weight reduction studies on vehicle bodies have gained great importance. Foam core sandwich structures stand out as the most ideal materials in terms of providing both weight reduction and strength conditions in the bodies of electric individual and public transportation vehicles. In this study, EPP foams with two different densities were placed between aluminum plates and sandwich structures were obtained by combining the two structures with an EVA-based adhesive. Compression and bending behaviors of the produced sandwich structures were investigated under quasi-static and dynamic loading conditions. With the tests carried out, the strength of the sandwich structures and the amount of energy they absorb were calculated and compared experimentally. According to the results obtained, it was observed that the denser D2 foam exhibited approximately 1.4 to 2.05 times more strength than the lower density D1 foam in all tests. In terms of the energy they absorb, the D2 foam absorbs 1.25 to 2.5 times more energy than the other foam. Contrary to this situation, only the dynamic compression test occurred in the tests performed. When the post-damage behavior of the sandwich structures was examined, it was also observed that the D2 foam returned to a very similar dimensions to its original size, giving more of the deformation after the damage at the end of 72 hours.

Anahtar Kelimeler

• Sandwich Composite Structure
• Polypropylene Foam
• Energy Absrobing Structures
• Automotive Lightweighting

Kaynakça

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