Effect of Drilling-Induced Delamination on the Flexural Strength of GNPs-Reinforced Carbon Fiber Sandwich Composites

Abstract

In this study, the effect of drilling-induced delamination damage on the flexural strength of sandwich composites with 0.5% by weight GNPs (graphene nanoplatelets) reinforced carbon fiber face sheets (GNPs/carbon sandwich) and nanoparticle-free Neat/carbon sandwich composites was investigated. In three-point bending specimens, drilling operations were performed with hole diameters of 5 mm and 6 mm. Delamination damage at the entry and exit points of the holes were observed through microscopic imaging and evaluated. Image processing techniques were applied to microscopic images, and quantitative values were obtained. According to the three-point bending test results, the lowest strength loss was observed in GNP/carbon sandwich composites. The highest bending strength was measured as 800 N in GNP/carbon sandwich composites. The lowest bending strength was found to be 450 N in pure/carbon sandwich composites drilled with a 6 mm diameter hole. Adding GNPs nanoparticles to carbon fiber sandwich composites reduced delamination damage caused by drilling. GNPs-reinforced sandwich composites showed better bending strength compared to sandwich composites without nanoparticles.

Keywords

• Graphene nanoplatelets (GNPs)
• Sandwich composites
• Delamination damage
• Drilling process
• Flexural strength

Supporting Institution

This study was supported by Selçuk University Scientific Research Projects Coordination Office (BAP) with project number 19301010.

Ethical Statement

The authors declare that the principles of scientific research and publication ethics were followed at all stages of the study.

Delme Kaynaklı Delaminasyonun GNP Takviyeli Karbon Fiber Sandviç Kompozitlerin Eğilme Dayanımı Üzerindeki Etkisi

Abstract

Bu çalışmada, delme kaynaklı delaminasyon hasarının %0,5 ağırlık oranında GNPs (grafen nanoplakacıklar) takviyeli karbon fiber yüzeyli sandviç kompozitlerin (GNPs/karbon sandviç) ve nanopartikül içermeyen Neat/karbon sandviç kompozitlerin eğilme dayanımına etkisi araştırılmıştır. Üç nokta eğme numunelerinde 5 mm ve 6 mm delik çaplarında delme işlemleri gerçekleştirilmiştir. Delik giriş ve çıkış bölgelerindeki delaminasyon hasarı mikroskobik görüntüler kullanılarak değerlendirilmiştir. Mikroskobik görüntülere görüntü işleme teknikleri uygulanmış ve kantitatif değerler elde edilmiştir. Üç nokta eğme testi sonuçlarına göre en düşük dayanım kaybı GNPs/karbon sandviç kompozitlerde gözlenmiştir. En yüksek eğilme dayanımı GNPs/karbon sandviç kompozitlerde 800 N olarak ölçülürken, en düşük eğilme dayanımı 6 mm çapında delinen Neat/karbon sandviç kompozitlerde 450 N olarak bulunmuştur. Karbon fiber sandviç kompozitlere GNP eklenmesi, delme kaynaklı delaminasyon hasarını azalttı ve nanopartikül içermeyen sandviç kompozitlere kıyasla eğilme dayanımında daha az bozulmaya yol açtı.

Keywords

• Grafen nanoplakalar (GNP
• Sandviç kompozitler
• Delaminasyon hasarı
• Delme işlemi
• Eğilme dayanımı

Supporting Institution

Bu çalışma,Selçuk Üniversitesi Bilimsel Araştırma Projeleri Koordinasyon Ofisi (BAP) tarafından 19301010 numaralı proje ile desteklenmiştir.

Ethical Statement

Yazarlar, çalışmanın tüm aşamalarında bilimsel araştırma ve yayın etiği kurallarına uyulduğunu beyan eder.

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