Study of fiber modulus effect on impact energy absorption characteristics of composite laminates at normal and oblique impacts

In this paper, the energy absorption characteristics of CFRP (Carbon Fiber Reinforced Polymer) laminates with different fiber modules under normal and oblique impacts are studied. The quasistatic basic mechanical properties test and low-speed drop weight impact test are carried out, and the inner damage is detected by C-scan. The material model includes the inter-laminar material model and the intra-laminar material model. The latter material model is calculated by the micro-mechanical method. The homogeneous method is used in each finite element calculation time step, and the cohesive element is used between the layers. The results of simulation and experimental are close. The impact angles of six fiber modulus composite laminates are evaluated by the four impact angles of 0 degrees, 10 degrees, 20 degrees and 30 degrees. The impact parameters, such as maximum contact force and contact time, are found linearity changes along with the impact angle and fiber modulus. However energy absorption presents a non-linear relationship to impact angle and fiber modulus. It is found that the reason is caused by the intra-laminar mechanical behavior. For the T300 CFRP, when the impact angle is less than 20 degrees, the energy absorption differs by only 3%, and the impact angle has little effect on energy absorption.