Influences of adherent thickness, temperature and velocity on strength of adhesively-bonded single-lap joints

In order to explore the failure mechanism of the structures with adhesively-bonded single-lap joints, a Hopkinson tension bar technique was applied to investigate influences of adherent thickness, temperature and velocity (the maximum velocity at the end of the specimen) on the strength of this kind of joint. Experimental results show that the strengths of the specimens tested increase with the increase of the adherent thickness and velocity and the decrease of the temperature. The finite element method was adopted to analyze the stress distribution in the adhesive layer. Analysis displays that shear stress affects the strength of the specimen more dominatingly than peel stress. An influencing factor, which was the value of peel stress divided by shear stress, was introduced to further discuss the effect of peel stress on the strength of the specimen. Further discussions indicate that the effect of peel stress decreases with the increases of adherent thickness and velocity and the decrease of temperature.