Impact behavior of multi-layer carbon skin composite sandwich panels with 3D spacer fabric

For this study, the strengths against impact effects of multi-layer composite sandwich panels reinforced by additional lamination structures using 3D spacer fabric have been investigated. To determine the impact strengths of the produced sandwich panels, falling weight tests with a constant impact energy of 15 J were performed on all of the samples, and the loads and absorbed energy were monitored as a function of time. In addition, the damage mechanisms occurring in the structure during impact were examined. Overall, according to the analysis of the damaged surface, the different impacts created a regional penetration area. Furthermore, no deviation in the breakdown of the surface texture was observed in the regions outside of the penetration area.