Finite Element Investigation of Performance of Composite-Steel Double Lap Adhesive Joint Under Tensile Loading

Abstract

Parametric study of composite-steel double lap joint under tensile loading is performed using finite element modeling. The joint is such that steel is placed between a straight and a curved composite sublaminate. Three joint characteristics including maximum Von Mises stress in adhesive layer, stiffness and weight are investigated. Design curves are provided to study the influence of geometric parameters on the joint behavior to determine the joint performance. The curves illustrate sensitivity of three mentioned joint characteristics to geometric variations. Selected parameters are adhesive thickness, overlap length, composite sublaminates' thickness and stiffness ratio. Results indicate variation of parameters may have either significant or negligible influence in the performance of the joint. Results also show that variation in geometric parameters does not make monotonous change in the performance of the joint and in some cases rate of the changes may differ. From the prepared curves it can be understood that increase in overlap length and adhesive thickness will decrease maximum Von Mises stress in adhesive layer and global stiffness of the joint. In case of sublaminate thickness decrease in the thickness of straight sublaminate leads to decrease in maximum stress in adhesive layer while the stiffness is increased. For the stiffness ratio an optimized point can be found beyond which maximum stress will increase. Global stiffness of the joint increases by increase in stiffness ratio. Changes in weight of the joints are easily calculated from the geometry and are reported in the text.