Rapid progress in the interdisciplinary field of automotive engineering and the pressing need for an environmental friendly alternative to metal and synthetic fiber-reinforced composites for vehicle structure have triggered recent research in the field of natural fiber-based composites. Their potential advantages are attributed to their light weight, low cost and biodegradability. However, their usage in present day automotive systems is restricted due a lower magnitude range of mechanical properties and limited study in this area. In contrast to mechanical joints, the adhesively bonded joints aid in reducing stress concentration, joining of dissimilar materials, corrosion prevention, weight reduction and a smoother finish. Thus, in the present study, failure load, and mean shear stress of single lap shear and double lap shear joints as a function of joint overlap length, are evaluated using a two part epoxy adhesive made by Huntsman. Initially, the specimens are tested according to the reference test methods specified in ASTM D5868 and ASTM D3528 standards, and the overlap length is then varied to determine the failure load and the mean shear strength at failure in respective conditions. It has been observed that higher curing temperatures give rise to only marginally high failure load and mean shear stress at failure compared to curing at room temperature. It has been found that with increasing overlap length, failure load increases and mean shear stress at failure decreases, in both single lap and double lap joints. It is further noticed that delamination is the dominant type of failure observed in both single lap as well as double lap joints.
