IMPROVING THE STRENGTHS OF METAL-METAL BONDING VIA INCLUSION OF GRAPHENE NANOFLAKES INTO ADHESIVE JOINTS Vijay S. Swarna, Ibrahim Alarifi, Vamsidhar R. Patlolla and * Ramazan Asmatulu Department of Mechanical Engineering Wichita State University, 1845 Fairmount, Wichita, KS, 67260-0133 *Email: ramazan.asmatulu@wichita.edu ABSTRACT The present study was aimed at improving the mechanical performance of epoxy based structural joints in aerospace, automotive, construction and marine industries. Epoxy adhesives have many applications in various industries, due to their exceptional material properties like flexibility, low maintenance, uniform stress distribution, durability and cost effectiveness. Single lap joints were prepared from Aluminum 2014-T3 and Magnolia 6380 epoxy adhesive. These single lap joints were tested according to specifications of ASTM-D1002 to evaluate the mechanical performance mainly shear strength of epoxy adhesive. The surface preparation procedures were carried out to enhance the adhesion between epoxy and aluminum test specimens. Graphene nano-flakes were added into the epoxy at 0, 0.5, 1, 2, and 3 weight percentages (wt%), to improve the load carrying capacity and efficiency of adhesive joints. Three test specimens of single lap joints were prepared for each sample and shear tests were conducted using MTS-Tensile machine to evaluate shear strength of an adhesive joint. It was observed that the load bearing capacity and shear strength of the adhesive joints were improved due to the inclusion of graphene nano-flakes into the epoxy. The major improvements were observed at 0.5wt% and 1wt% graphene inclusions by 1.37% and 10.43% increase in shear strength, when compared with baseline test coupons. Keywords: Graphene nano-flakes, Adhesive joints, Single lap joints, Nanocomposite, Mechanical Strength, Metal-Metal Bonding. 1. INTRODUCTION 1.1 Adhesive Joints Most structural units fail at joints as they are a source of stress concentration. An improper design would also lead to increase in the stress concentration, which would further decrease the service life of a structural component. Adhesive joints, play major role in many industries, such as aerospace, mechanical, automotive, construction and marine [1, 2]. Different types of adhesive joints including single, butt, double, and tapered joints are chosen for various roles. The main advantage of these adhesive joints over mechanical joints (fasteners) is that, they considerably reduce concentrated loads, vibrational stresses, fatigue failures, corrosion