Behaviour of continuous fibre composite sandwich core under low-velocity impact

Abstract This article describes an experimental study of the impact behaviour of a novel composite corrugated core sandwich structure under low-velocity impact. Influences of geometric parameters of the novel sandwich core, such as thickness, height, and short span length were studied. Four different configurations of composite corrugated core sandwich structures were prepared and tested. The impact events were monitored using a high-speed camera and measured by an impact force transducer and accelerometer attached to the impactor. The results revealed that the increase of core thickness improved impact capacity while the increase of core height decreased sandwich strength by increasing elastic deformation. The damage status of the novel composite core sandwich was simulated and insight into the damage mechanism was gained with finite element analysis. This study proposes an improved numerical model by incorporating the effect of the impactor head which was able to predict the impact capacity to within 10% variation of the experimental results. The results also identified that the multi-cell composite corrugated core increased the impact capacity due to the continuity of the fibres between adjacent cells. Moreover, the trapezoidal composite corrugated sandwich core showed higher specific strength compared to traditional honeycomb, truss and foam cores.