Ballistic and delamination mechanism of CFRP /aluminum laminates subjected to high velocity impact

This work focus on the experimental study of ballistic and delamination mechanism on carbon/epoxy laminates with [-45/90/45/0] stacking sequence. A series of impact tests were carried out on the monolithic CFRP and Al/CFRP/Al laminates targets. The two targets were compared in terms of ballistic limit, energy absorption, penetration process, damage mechanism and interfacial delamination. Results showed that the Al/CFRP/Al laminates with equal thickness had better ballistic performance than that of the monolithic CFRP laminates. The delamination of adjacent layers was mainly controlled by bending moment, uneven stress distribution of interface and mismatch of wave impedance between layers with different lay-up directions. The shear wave propagated between fiber layers in different layering directions, resulting in interlayer crack extension.