The effects of surface roughness and bond thickness on the fatigue life of adhesively bonded tubular single lap joints

Abstract Since the surface roughness of adherends greatly affects the strength of adhesively bonded joints, the effect of surface roughness on the fatigue life of adhesively bonded tubular single lap joints was investigated analytically and experimentally by a fatigue torsion test. The stiffness of the interfacial layer between the adherends and the adhesive was modelled as a normal statistical distribution function of the surface roughness of the adherends. From the investigation, it was found that the optimum surface roughness of the adherends for the fatigue strength of tubular single lap joints was dependent on the bond thickness and applied load. Keywords: ADHESIVELY BONDED TUBULAR SINGLE LAP JOINTFATIGUE STRENGTHOPTIMUM SURFACE ROUGHNESSINTERFACIAL LAYERSTATISTICAL DISTRIBUTION OF STIFFNESS