Experimental analysis of carbon nanofibers reinforced epoxy adhesive bonded joints made with composite materials

Abstract Today adhesive joints with use of composite materials has many applications. Light weight, sealing capability, with high resistance to fatigue, all of the features of this unique connection that enables the designer to create a cost-effective connectivity. The aim of this project is to evaluate the adhesive strength of the one edge adhesive joints under impact and stretch loading and different thermal cycles. Epoxy (LY219, HY5161) is used as adhesive. Several studies in recent years show that adding a few percentages of Nanoparticles into the resin, can improve the mechanical and thermal properties to an acceptable level. This article examines the mechanical behavior of epoxy adhesive joints reinforced with nanoparticles of carbon nanofibers (CNFs). The amount of carbon nanofibers into the resin particles consists of 1%, 3% and 5% of the whole resin weight. Particles by hand stirring and ultrasonic devices are uniformly distributed within the resin. The composite adherend (binder) surfaces were prepared according to ASTM D2093-97. According to ASTM D3165-95, the properties of the reinforced adhesive in shear were obtained by tension loading of single lap joint specimens. Glass/polyester composite adherends are made with hand lay-up and sheet molding compound (SMC) methods. The results showed that the adhesive joints (hand lay-up and SMC) with 1% carbon nanofibers had the maximum strength in tensile loading and the highest values of Charpy impact energy, that for adherends made by hand lay-up method, this maximum value occurs in 5 and 0 thermal cycles respectively.