Hybrid composite-metal structure response to post-impact compression – Experimental and numerical study

Numerical analysis of the post-impact damage propagation process during CAI tests on titanium-based fibre metal laminates was conducted, and the model was validated by collation of mechanical parameters predicted by it with experimental results. Delaminations induced by the impact were claimed as the hotspot for other modes propagation in most of studied cases and intensively propagated shortly before reaching peak compressive force. Metal – composite interfaces away from impact surface were locations of most intensive delamination propagation during CAI, constituting 63.5 % of overall damage area for titanium-carbon laminate and 81.6 % for titanium-glass laminate. Similarly to delaminations, damage due to fibre and matrix compression propagated from impact point and lead to significant load-carrying ability loss even in low volumes. Propagation of fibre and matrix tension was connected more to buckling progression, than post-impact damage and had the highest volumetric share in composite layers damage modes (max 13.5 % for titanium-carbon laminate and 8.3 % for titanium-glass laminate).