Low-velocity impact resistance of repaired honeycomb sandwich composites

Abstract

The honeycomb core replacement scarf repair method was used to repair the one side face-sheet and honeycomb core damage of aluminum honeycomb sandwich composite plate. The drop hammer impact tests were carried out on the intact honeycomb sandwich panel and the repaired honeycomb sandwich panel, and the influence of honeycomb core replacement scarf repair on the impact resistance properties was compared and analyzed. X-ray digital imaging technology and macroscopic observation were used to investigate the damage forms and internal failure mechanisms of composite repair structure under the low velocity impact. The residual compression property after impact was characterized. The results show that with the increase of impact energy, the damage areas of both intact and repaired honeycomb sandwich panels are increased, the damage area of intact honeycomb sandwich panel is larger than that of repaired ones under the same impact energy. The impact load curve type of repaired honeycomb sandwich panel is changed completely, and the repaired honeycomb sandwich panel shows better impact resistance. Under the same impact energy, the CAI strength of the repaired honeycomb sandwich panel is higher than that of the intact ones. The failure mechanism includes the expansion of impact damage and compression damage. The impact resistance of the honeycomb splicing area is the best.

Keywords

• honeycomb sandwich composite
• scarf repair
• low velocity impact
• compression after impact(cai)
• failure mechanism