Delamination Buckling and Crack Propagation Simulations in Fiber-Metal Laminates Using xFEM and Cohesive Elements

Abstract

Simulation of fracture in fiber-reinforced plastics (FRP) and hybrid composites is a challenging task. This paper investigates the potential of combining the extended finite element method (xFEM) and cohesive zone method (CZM), available through LS-DYNA commercial finite element software, for effectively modeling delamination buckling and crack propagation in fiber metal laminates (FML). The investigation includes modeling the response of the standard double cantilever beam test specimen, and delamination-buckling of a 3D-FML under axial impact loading. It is shown that the adopted approach could effectively simulate the complex state of crack propagation in such materials, which involves crack propagation within the adhesive layer along the interface, and its diversion from one interface to the other. The corroboration of the numerical predictions and actual experimental observations is also demonstrated. In addition, the limitations of these numerical methodologies are discussed.