Damage tolerant behaviors of a biomimetic CFRP laminate

The present work examines the damage tolerant behaviors of synthetic composites by using composite architectures observed in biological materials. The static, impact, and compression after impact (CAI) behaviors of biomimetic CFRP laminates with stacking sequences similar to those found in animal hard tissues are compared to those of a standard quasi-isotropic and a cross-ply laminates. The dependence of the extent of damage in the samples with a hole under tensile loading on the laminate lay-up was analyzed by a finite element analysis. The damage tolerance is then related to the actual damage extension from the hole perpendicularly to the applied load. It is shown that the damage tolerance of biomimetic laminate is more advantageous than the two other laminates. The implications of the findings for the design of damage-tolerant laminates are further discussed. It is also shown from the results of compression after impact test that the sensitivity of biomimetic laminate to the presence of delamination damage is significantly lower than that of quasi-isotropic and cross-ply laminates.