A four-point bending test to study both failure initiation and crack propagation at the interface of an adhesive joint

Pierre Bidaud (1) , Nicolas Carrere (1) , Thomas Bonnemains (1) , Eric Lolive (1)

1 IRDL - Institut de Recherche Dupuy de Lôme

In this study the authors propose a test specimen developed to study both failure initiation and crack propagation at the interface with the aim to determine its strength and toughness. The two-substrate specimen used were bonded with a thin joint of structural adhesive, to conform to most of the industrial applications. Then, geometry of the specimen and parameters of the four-point bending were designed to localize failure initiation at one interface and in order to have a stable evolution of the crack propagation at this interface. This optimization work was performed using 3D Finite Element Model for an interface of metallic substrates and an industrial epoxy based adhesive. An experimental campaign was carried out on the optimized configuration of the specimen and the four-point bending flexural loading. The failure properties identified at the interface for a specific surface preparation are compared to the one characterized for “cohesive” failures on the structural adhesive

Mots clés: Adhesive; Interface; Fracture mechanics; Failure initiation; Crack Propagation

Domaines: Matériaux; Mécanique [physics.med-ph]

Pierre Bidaud, Nicolas Carrere, Thomas Bonnemains, Eric Lolive. A four-point bending test to study both failure initiation and crack propagation at the interface of an adhesive joint. 20th European Conference on Composite Materials: Composites Meet Sustainability, ECCM 2022, Jun 2022, Lausanne (CH), Switzerland. pp.662-665. ⟨hal-04060359⟩