Mechanical responses of CFRP/PVC foam sandwich plate impacted by hailstone

• Published in: International journal of impact engineering 2023-08, Vol.178, p.104631, Article 104631
• Main Authors: Zhou, Yong, Xue, Bin, Guo, Yunxin, Zhang, Weiping, Wang, Renpeng
• Format: Article
• Language: English
• Subjects: CFRP/PVC foam sandwich structures; Delamination; Hailstone; Impact; Numerical analysis
• ISSN: 0734-743X; 1879-3509
• DOI: 10.1016/j.ijimpeng.2023.104631

•CFRP/PVC foam sandwich panels were experimentally studied under the hailstone impact with different incident angles and impact speeds.•Maximum displacement and matrix cracking area is proportional to the vertical kinematic energy of hailstone.•Relationship between the delamination area and vertical kinematic energy of hailstone is nonlinear.•Comprehensive parametric analysis was performed based on LS-DYNA package.•Failure mode changes with the span-to-thickness ratio of the sandwich panel. Mechanical responses of sandwich plate with carbon fiber reinforced polymer (CFRP) laminate as face-sheets and polyvinyl chloride (PVC) foam as core, which is promising in the lightweight design of high-speed maglev trains, was studied for the case of hailstone impact. Nine 500 × 500 mm sandwich plate specimens of three face-sheet thicknesses 1, 2 and 3 mm and a constant core thickness 30 mm were fabricated and tested under the impact of ice spheres of 50 mm in diameter propelled by the first-stage light gas gun. Three impact speeds, i.e. 30, 60 and 90 m/s, of the ice spheres and three incident angles, i.e. 0°, 30° and 45°, were investigated. For all cases, no macro failures were observed, but invisible damages, i.e. delamination in the upper face-sheets and indentation of the foam core, were found by high resolution ultrasonic testing. The experimental results were then used to calibrate the corresponding numerical model, based on which a thorough parametric analysis was performed to show the full dynamical responses of CFRP/PVC foam sandwich panels under hailstone impact. It is found that the foam cushion could effectively protect the rear face-sheet and increasing the ratio of span to thickness of the panel could reduce the damage degree due to the change of failure mode from local to global.