Assessment of the effect of pre-impact loading on the residual strength and fatigue life of additively manufactured composite sandwich panels

This study is dedicated to the investigation of the influence of the pre-impact loading on the residual properties of composite sandwich panels. The methodology was proposed for pre-impact testing followed by quasi-static and cyclic tension of structurally representative composite specimens and structural elements. The material was additively manufactured sandwich panels consisted of honeycomb core made of acrylonitrile butadiene styrene (ABS) thermoplastic and two load-bearing face sheets made of ABS reinforced with 15% carbon fibers. Novel experimental data was obtained on the residual load-bearing capacity and fatigue life after pre-impact loading at various impact energy. Several phenomenological models were used to approximate obtained data on impact sensitivity, that demonstrated high descriptive ability.