In  High-Velocity Impact and Delamination Analysis of Hybrid Composite Plate with VUMAT project, the bullet hits the plate. In fact, this composite plate is in the form of a hybrid composite or a combination of various types of glass-epoxy and carbon-epoxy  with different angles, which cohesive element are used in between composite layers. Due to the fact that the impact speed is high, a special method must be used to model the composite damage. It should be mentioned, the method of application is based on the matznmiller model and the reduction of the gradual properties and the effects of the presence of adhesive between the layers are also considered. The simulation uses VUMAT subroutine, which is about 1,000 lines long.

Impact tutorial package with VUMAT subroutine & Impact analysis in unidirectional composites:

3D continuum Abaqus HASHIN progressive Damage for composite materials (VUMAT Subroutine)

Simulation of Unidirectional Composite Damage in ABAQUS