Hibrit kompozitlerin yağmur suyu altındaki burkulma davranışının incelenmesi

Öz

Kompozit malzemeler, üstün mekanik özellikleri sayesinde her geçen gün kara, hava ve deniz araçlarının yapımında yaygın olarak kullanılmaktadırlar. Hava, kara ve deniz araçları, uygulama alanlarında sıklıkla yağmur suyuna maruz kalabilmektedir. Bu çalışmada, hibrit kompozitlerin burkulma dayanımına yağmur suyunun etkisini deneysel olarak araştırılmıştır. Bu amaçla karbon, E-cam ve aramid liflerinin farklı kombinasyonlarından oluşan katmanlı hibrit kompozit plakalar üretilerek burkulma deneyi numuneleri elde edilmiştir. Hibrit kompozit numuneler üç gruba ayrılmıştır. İlk grup kontrol grubu olarak belirlenmiş ve 60 gün boyunca kuru ortamda tutulmuştur. İkinci grup 60 gün boyunca yağmur suyunda bekletilmiştir. Üçüncü grup ise 60 gün boyunca 1 gün yağmur suyunda ve 1 gün kuru ortamda bekletilmiştir. Bekleme süreleri dolan numunelere 100 kN kapasiteli Shimadzu AG-X üniversal test cihazı ile burkulma testi uygulanmıştır. Testler 1 mm/dk sıkıştırma hızında yapılmış ve her numune tipi için üç test gerçekleştirilmiştir. Elde edilen sonuçların ortalaması alınarak numunelere ait burkulma dayanımları elde edilmiştir. Deneylerden elde edilen veriler doğrultusunda hibrit kompozit numunelerin burkulma davranışları incelenmiştir. Çalışmanın bulgularına göre, yağmur suyunda bekletmenin kritik burkulma yüklerini, kuru ortama kıyasla düşürdüğünü ortaya koymaktadır. Sonuçlar, [(0/90)3]s istifleme dizilimiyle üretilen CAG numunelerinin burkulmaya karşı en yüksek direnci gösterdiğini, buna karşılık [(45/-45)3]s istifleme dizilimine sahip CAG45 numunelerinin en düşük kritik burkulma yükü değerine sahip olduğunu ortaya koymaktadır.

Anahtar Kelimeler

• Burkulma
• hibrit kompozit
• istifleme dizilimi
• yağmur suyu etkisi

An investigation into the buckling behavior of hybrid composites under rain water exposure

Abstract

Composite materials are increasingly used in the construction of land, air, and sea vehicles due to their superior mechanical properties. These vehicles are often exposed to rainwater in their areas of operation. In this study, the effect of rainwater on the buckling strength of hybrid composites was experimentally investigated. For this purpose, layered hybrid composite plates were produced using different combinations of carbon, E-glass, and aramid fibers, and specimens for buckling testing were prepared. The hybrid composite specimens were divided into three groups. The first group was designated as the control group and kept in a dry environment for 60 days. The second group was immersed in rainwater for 60 days. The third group was alternately kept in rainwater for one day and in a dry environment for the next day, for a total of 60 days. After the conditioning period, buckling tests were conducted on the specimens. The tests were performed using a Shimadzu AG-X universal testing machine with a capacity of 100 kN, at a compression speed of 1 mm/min, and three tests were conducted for each specimen type. The average of the obtained results was taken to determine the buckling strength of the specimens. The buckling behavior of hybrid composite specimens was investigated based on the data obtained from the experiments. The study's findings reveal that exposure to rainwater reduces critical buckling loads compared to a dry environment. The results show that CAG specimens produced with a [(0/90)3]s stacking sequence have the highest resistance to buckling, whereas CAG45 specimens with a [(45/−45)3]s stacking sequence have the lowest critical buckling load value.

Keywords

• Buckling
• hybrid composite
• stacking sequence
• rain water effect

Kaynakça

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