High-velocity impact damage behavior of hybrid fiber reinforced epoxy composites

This paper is aimed to perform a numerical simulation study on the high-velocity impact failure behavior of hybrid fiber reinforced epoxy composite laminates based on the finite element model. Firstly, quasi-static mechanical tests of pure carbon fiber reinforced epoxy composites and pure aramid fiber reinforced epoxy composites were carried out to obtain their basic mechanical properties. Then, high-velocity impact tests were conducted to determine the critical penetration velocity and explore the influence of hybrid ratio on the impact resistance of hybrid composite reinforced composite laminates. The finite element model of high-velocity impact for hybrid fiber laminates was established, and the progressive damage constitutive of composite laminates was developed on the basis of the Murakami-Ohno damage evolution theory. The strain rate effect coefficient was introduced to consider strain rate dependency, and the element deletion was co-controlled by damage variable and element distortion in parallel. Then the high-velocity impact simulation for different hybrid ratio laminates was carried out and the corresponding critical penetration velocity was obtained respectively. The experimental results of high-velocity impact show that the critical penetration velocity increases with the increasing hybrid ratio, exhibiting a positive hybrid effect. Compared with the experimental results, the proposed model can accurately predict the quasi-static mechanical response and high-velocity impact response for the hybrid fiber reinforced epoxy composites, and the difference of the critical penetration velocity is less than 4.5%.