Effect of Tungsten-Cobalt (WCo) nanoparticles on shear and flexural strength of adhesive joints

Öz

The effects of Tungsten Cobalt (WCo) nanoparticle contribution on the shear and bending strengths are examined in adhesively bonded single-lap joints made with glass fiber-reinforced polymer (GFRP) substrates in this study. WCo particles were synthesized via mechanical alloying and added to epoxy adhesives at varying concentrations (1.0, 3.0, and 5.0 wt.%). The adhesive mixtures were used to bond GFRP plates in single-lap joints (SLJ), and their mechanical performance was evaluated under shear and bending loading conditions. The shear strength results indicate that the incorporation of 1.0 wt.% WCo increased shear strength by 68.5%, while 3.0 wt.% WCo yielded the highest improvement at 136%. However, the addition of 5.0% WCo led to a reduced enhancement (60%) due to nanoparticle agglomeration and local stress concentrations. Notably, the maximum bending stress was observed in the 3% WCo-containing specimens. Specifically, the bending load increased by 51.5%, from 61.96 MPa in the pure epoxy specimen to 93.85 MPa in the 3% WCo-reinforced specimen. Failure surface analysis revealed that WCo-reinforced samples exhibited light-fiber tear, thin-layer cohesive failures, and enhanced bonding properties due to increased viscosity and the filling of micro-voids. These findings suggest that WCo nanoparticles effectively improve the shear and bending performance of epoxy adhesives by enhancing interfacial bonding, ductility, and stress distribution mechanisms. The study provides insights into the potential of WCo-reinforced adhesives as a cost-effective and high-performance solution for engineering applications.

Anahtar Kelimeler

• WCo nanoparticles
• Epoxy adhesive
• Single-lap joints (SLJs)
• Shear strength
• Flexural performance
• Failure modes

Tungsten-Kobalt (WCo) nanoparçacıklarının yapıştırma bağlantılarının kayma ve eğilme dayanımlarına etkisi

Öz

Bu çalışmada cam elyaf takviyeli polimer (GFRP) altlılarla yapılmış tek bindirmeli yapıştırma bağlantılarında Tungsten-Kobalt (WCo) parçacık katkısının kayma ve eğilme dayanımlarına etkileri incelenmektedir. WCo parçacıkları mekanik alaşım yöntemi ile sentezlenmiş ve epoksi yapıştırıcısına farklı konsantrasyonlarda (ağırlıkça % 1.0, 3.0 ve 5.0 ) eklenmiştir. Bu yapıştırıcı karışımları, GFRP plakalarını tek bindirmeli eklem (SLJ) şeklinde bağlamak için kullanılmış ve mekanik performansları kayma ve bükülme yükleri altında değerlendirilmiştir. Kayma dayanımı testleri, %1.0 WCo eklenmesinin kayma dayanımını %68.5 artırırken, %3.0 WCo katkısının %136 ile en yüksek iyileşmeyi sağladığını göstermiştir. Ancak %5.0 WCo eklenmesi, nanoparçacıkların topaklanması ve yerel gerilme yoğunlukları nedeniyle %60’lık daha az bir iyileşme ile sonuçlanmıştır. Dikkate değer bir şekilde, maksimum eğilme gerilmesi %3 WCo içeren numunelerde gözlemlendi. Özellikle, eğilme dayanımı %51.5 artarak, saf epoksi numunesinde 61.96 MPa iken %3 WCo takviyeli numunede 93.85 MPa'ya yükseldi. Hata yüzey analizi, WCo takviyeli örneklerde ince lif çekilmesi, ince tabaka kohezif arıza türleri ve mikro boşlukların dolması ile birlikte viskozite artışı nedeniyle geliştirilmiş bağlama özellikleri sergilediğini ortaya koymuştur. Bu bulgular, WCo nanoparçacıklarının arayüzey bağlanmasını, sünekliği ve gerilme dağılım mekanizmalarını iyileştirerek epoksi yapıştırıcılarının kayma ve eğilme performansını etkili bir şekilde artırdığını göstermektedir. Çalışma, WCo takviyeli yapıştırıcıların, mühendislik uygulamaları için maliyet açısından etkin ve yüksek performanslı bir çözüm olma potansiyeline sahip olduğunu vurgulamaktaydı.

Anahtar Kelimeler

• WCo nanoparçacıkları
• Epoksi yapıştırıcı
• Tek katmanlı eklemler (SLJ
• Kayma dayanımı
• Eğilme performansı

Kaynakça

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