Design, Manufacturing, and Evaluation of Functionally Graded Adhesive Lap Joints Using Radiation Sensitive Adhesives

Grading adhesive properties across a bondline can lead to more unniform stresses and increased strength without altering the geometry of the adherends. In this study, radiation sensitizers were added to adhesives to create a secondary cross-linking that is activated with radiation. In this way the adhesive stiffness and strength can be tailored spacially by controlling the exposure to radition along the bondline. In this paper, designing manufacturing, and testing radiation sensitive functionally graded adhesive joints was performed. The study was not able to conclusively show that the functionally graded single lap joints were stronger than a regular joint, but it did allow for a detailed analysis on what methods and tools could be improved or scaled up for industrial applications of this technology.