In-plane fracture analysis of bi-material adhesively bonded joints by using a simple bend beam specimen

Abstract

In the present work, a new and novel test specimen is presented to solve the difficulties and problems of traditional adhesive fracturing test specimens. The specimen is a bi-material adhesive joint in the shape of a rectangular beam and containing a vertical crack in the adhesive layer. If the specimen is loaded by a three-point bend setup with symmetric or asymmetric bottom span supports relative to the crack, opening deformation any desired combination of opening and shear deformations is achieved, respectively. The results demonstrated that the proposed test specimen could be used to introduce the full range of mode mixities from pure opening mode to pure shearing mode for adhesively bonded joints with similar and dissimilar adherents (such as Alumina and Aluminum) by changing the position of the bottom span supports. The variations of mode I and mode II geometry factors, normalized T-stress, biaxiality ratio, crack tip plastic zone and also the direction of fracture initiation angle are also presented for the analyzed test specimen by using the ABAQUS commercial code. As a result, the suggested specimen can be recommended as a potential candidate specimen for fracture studies of adhesively bonded joints subjected to in-plane loading conditions.