A Study of Dynamic Tensile Shear Strength of Adhesively Bonded Single Lap Joints at Different Loading Temperatures, Velocities and Adherent Thicknesses

Abstract

This paper studies the shear strength of adhesively bonded single lap joints subjected to impact loads by means of split Hopkinson tensile bar. The experiments were conducted at two velocities (V=20m/s, 6.67m/s), three testing temperatures (T=-40℃, 20℃, 80℃) and two adherent thicknesses (L=0.75mm, 2.25mm). The results indicated that the shear strength of the specimen decreased with the increase of temperature and increased with the increase of velocity and adherent thickness. By means of FEM modeling and examination of the failure morphology of the specimen, it was found that given the other constant parameters, the elevation of temperature or the reduction of velocity and adherent thickness would cause the increase of peel stress in the adhesive, which was mainly responsible for the expansion of cracks toward the interface between the adhesive and the steel plate, resulting in the degradation of the mechanical property of the specimen.