Experimental and Simulation Study on the Effect of Adhesive Thickness on Mode I Fracture Toughness

doi:10.3901/JME.2018.10.043

Abstract

Abstract: Structural adhesive bonding has many advantages over traditional connection methods and has gained wide application in various industrial fields. As adhesive layer plays a key role in the load transfer of bonded structure, it becomes essential to understand the mechanism of crack propagation in the adhesive layer. A combined experimental-numerical method is proposed using double cantilever beam and cohesive zone model; to study the effect of adhesive thickness on Mode I fracture toughness. In order to overcome the difficulty in the accurate measurement of crack length, a compliance-based beam method is developed to obtain the Mode I fracture toughness data. A bilinear cohesive zone model is introduced to simulate the crack propagation behaviour in the adhesive layer. The load-displacement curve, R curve and Mode I fracture toughness data obtained from both experiment and simulation are analysed to validate the FE model. It is observed that adhesive thickness has significant influence on the fracture behaviour of adhesive under Mode I loading condition. The Mode I fracture toughness shows a concave trend with the increase of adhesive thickness, while the failure mode of the fracture surface also changes from cohesive failure to mixed failure.

Key words: cohesive zone model, finite element simulation, fracture mechanics, fracture toughness, structural adhesive

CLC Number:

O346
U466

HAN Xiao, JIN Yong, YANG Peng, LI Xiaoyang, HOU Wenbin. Experimental and Simulation Study on the Effect of Adhesive Thickness on Mode I Fracture Toughness[J]. Journal of Mechanical Engineering, 2018, 54(10): 43-52.

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