Repeated low-velocity impact response and damage mechanism of glass fiber aluminium laminates

Glass fiber aluminium laminate (GLARE) is a kind of fiber metal laminates widely applied in aircraft structures, frequently subjected to low-velocity impact incidents. The purpose of this paper is to investigate the dynamic response and damage mechanism characterization of GLARE under single and repeated low-velocity impacts. Firstly, a progressive degradation finite element (FE) model was developed and validated. Three different failure criteria were compared to analyze the damage behavior of composites of GLARE in terms of accuracy and efficiency, wherein a user defined material subroutine VUMAT was introduced. Then, the validated model was used to study the influence of the impact angle. Four different impact angles including 30° 45° 60° and 90° were analyzed in terms of plastic deformation, impact contact force, energy absorption and internal damage. Finally, the simulation of GLARE subjected to repeated impacts was carried out, in which the cumulative damage effects were considered. The detailed dynamic response and damage evolution of aluminium layers and composite layers as well as their interfaces with the number of impacts increasing were revealed.