Damage Behavior Prediction of Repaired Composite Laminates Subjected to Oblique Penetrate Loading

Abstract

To predict the effect of oblique impact on the damage and performance of perforation resistance of repaired composite laminates, a three-dimensional continuum damage model (CDM) is used to simulate and calculate the low-velocity impact process of repaired laminates. In the established finite element model, several different types of failure modes are considered. The damage model is based on the modified 3D-Hashin failure criterion to predict the initial damage of the fiber and matrix. The linear-exponential law and the exponential law are used to simulate the tensile and compressive softening process of the material. The triangle traction-separation law and mixed-mode fracture energy method are applied to simulate interface debonding damage between patch/lamina, patch/patch and lamina/lamina. A comparison of the numerical results of several different offsets with the experimental results shows that the simulated failure modes and impact responses are very close to the experiment, which verifies the validation of the finite element model (FEM). The increase of the impact angle can enhance the residual velocity of the projectile in the laminate and reduces the energy absorption. At the same time, it has a great influence on the failure modes, especially the interface debonding damage of the patch.