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Fiber metal laminates have been successfully applied in military aircrafts, armor vehicles and other modern engineering industries as protective structures due to their outstanding impact resistant properties. Prediction of the ballistic performance and investigation on the damage mechanism of the fiber metal laminates under general oblique impact conditions still remain a very challenging issue. In this study, a nonlinear dynamic finite element model in terms of continuum damage mechanics including intra- and inter-layer failure modes is presented. The accuracy of this model is validated with available experimental data. The damage and ballistic performance of two different structural fiber metal laminates subjected to high-velocity oblique impact by rigid hemispherical nose projectile with angles of 0°, 30°, 45° and 60° are studied. The numerical results show that the projectile deflects when the oblique impact occurs and the deflection angle decreases with increasing the impact velocity. The residual velocity of the projectile and the energy absorption of the target are related to the initial impact velocity and impact angle of the projectile. The proposed simulation approach offers a new proper reference for numerical investigations of common oblique impact problems in other fiber metal laminates. [ABSTRACT FROM AUTHOR]

Abstract Fiber metal laminates (FMLs) have been widely used in many high-tech industries as protective structures because of their excellent impact resistance. The damage constitutive model that accurately characterizes the complex damage modes and failure processes of FMLs is the base to study the ballistic impact problems by numerical simulation. In this paper, a nonlinear finite element model based on continuum damage mechanics is established to investigate the damage modes and failure mechanisms of carbon fiber reinforced aluminum laminates (CRALLs) under high velocity impact. Johnson-Cook material model and a 3D rate-dependent constitutive model are applied to identify the in-plane damage in aluminum and fiber composite layers respectively; cohesive elements governed by bilinear traction-separation constitutive model are implemented to simulate the inter-laminar delamination induced by impact. The ballistic performance and damage characteristics of CRALLs under high velocity impact by projectiles with different shapes are studied in detail. The obtained numerical results correlate well with the available experimental data thus validates the proposed finite element model, which also provides an appropriate reference for numerical studies of high velocity impact issues in other FMLs. [ABSTRACT FROM AUTHOR]