An enhanced material model for the simulation of high-velocity impact on fiber-reinforced composites

Composite MSC (MAT_161 and MAT_162) is an enhanced material model for fiber-reinforced composites implemented in the software LS-DYNA which considers different failure modes in tension, compression and shear, with a progressive failure model. It allows to model delamination without the necessity of physical interface between the layers. Furthermore, it considers the effect of strain rate on the strength and moduli properties of the materials by means of a logarithmic function. Several studies can be found in the literature where the material model Composite MSC is implemented for modeling glass fiber-reinforced composites while it is difficult to find studies related to aramid fiber-reinforced composites. Aramid fibers are used in the manufacturing of ballistic shields since they are characterized by high tensile strength and resistance to impact damage. In this study the predictive accuracy of the material model Composite MSC (in particular MAT_162) for aramid fiber-reinforced composites is assessed simulating the high-velocity impact of a .357 Magnum projectile considering different impact velocities and therefore different scenarios from the arrest of the projectile to the full penetration of the target. MAT_162 is compared with MAT_058 which is a simpler material model which needs less input materials parameters and is therefore easier to be implemented. Furthermore, a parametric study on input parameters which are considered to be relevant is performed.