DETERMINATION OF MECHANICAL PROPERTIES OF STRUCTURAL ADHESIVES FROM ADHESIVELY BONDED JONTS SUBJECTED TO SHEAR LOAD

Yıl 2015, Cilt: 56 Sayı: 668, 48 - 55, 02.09.2015

Murat Demir Aydın Salih Akpınar Adnan Özel Sadık Erdoğan

Öz

Adhesively bonded structures are widely used in many industries such as aerospace, aeronautics, automotive and nautical fields. It is very important to determine accurate and reproducible mechanical properties of an adhesive layer in the adhesively bonded joints via experimental methods. In accordance with the design objectives, a widely used experimental method in the determination of the shear stress-shear strain curve for adhesives is the Thick Adherent Shear Test (TAST). The purpose of this method is to determine the adhesive properties from single lap joints subjected to shear load. In this study, the mechanical properties of adhesives from the joints prepared by using three different structural adhesives (SBT 9244, FM 73 and DP460) are measured via TAST method. Firstly, some experiments were conducted on the samples that were prepared by using FM 73 film adhesive. The obtained data were compared with the literature and system accuracy was controlled. At a later stage of the study, the shear stress-shear strain curves of SBT 9244 and DP 460 structural adhesives were determined. In conclusion, the TAST method is a very affective method of producing repeatable and accurate data in determining mechanical properties of structural adhesives.

Anahtar Kelimeler

Structural adhesives, mechanical properties

KAYMA YÜKÜNE MARUZ YAPIŞTIRMA BAĞLANTILARINDAN YAPISAL YAPIŞTIRICILARIN MEKANİK ÖZELLİKLERİNİN BELİRLENMESİ

Öz

Yapıştırma bağlantıları havacılık, uzay, denizcilik gibi birçok endüstriyel alanda yaygın bir şekilde kullanılmaktadır. Bir yapıştırma bağlantısı içindeki yapıştırıcı tabakasının mekanik özelliklerini doğru ve tekrarlanabilir bir biçimde deneysel yollardan belirleyebilmek son derece önemlidir. Tasarım amaçlarına uygun olarak yapıştırıcıların kayma gerilmesi-kayma gerinmesinin tespitinde oldukça sık kullanılan bir yöntem, TAST (Thick Adherend Shear Test) yöntemidir. Bu yöntemin amacı, kayma yüküne maruz yapıştırma bağlantısından yapıştırıcının gerilme-şekil gerinme davranışlarını tekrarlanabilir ve doğru bir biçimde belirlemektir. Bu çalışmada, üç farklı yapısal yapıştırıcı (SBT 9244, FM 73 ve DP 460) kullanılmıştır. Öncelikle, FM 73 film yapıştırıcısı kullanılarak hazırlanan numuneler üzerinde deneyler yapılmıştır. Elde edilen veriler, literatür ile karşılaştırılarak sistemin doğruluğu kontrol edilmiştir. Çalışmanın bir sonraki aşamasında ise SBT 9244 ve DP 460 yapısal yapıştırıcılarının kayma gerilmesi-kayma gerinmesi davranışları belirlenmiştir. Sonuçta, TAST yönteminin yapısal yapıştırıcılarının mekanik özelliklerinin belirlenmesinde tekrarlanabilir ve doğru veriler ürettiği görülmüştür.

Anahtar Kelimeler

Yapıştırıcılar, mekanik özellikler

Kaynakça

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