Effect of over-ply on moisture absorption behavior of scarf-repaired composite laminate

Abstract

The over-ply covering the bondline in scarf-repaired laminates can avoid direct exposure of the adhesive to moisture environment which would decrease the properties of the adhesive. The effect of the over-ply on moisture absorption behavior of scarf-repaired composite laminate was studied in this paper. 3D finite element models (FEMs) of scarf-repaired laminates with and without over-ply were established to simulate the moisture absorption behavior and verified by experimental results. Then these models were used to investigate the effects of some factors, including over-ply type, configuration, direction and number, on moisture absorption behavior of the repaired structures, especially of the adhesive. The results show that the over-ply can efficiently decelerate moisture absorption of the adhesive and delay the time of its moisture absorption equilibrium. Over-ply type has effect on moisture absorption of the adhesive. Woven over-ply is more effective to protect the adhesive in repaired laminates from moisture absorption than unidirectional over-ply. For the laminates with only large-circle bonding surface covered, over-ply lap length, configuration and direction are not very important parameters to affect the moisture

Investigations on toughening and self‐healing performance of plain woven composites with mendable polymer stitches

“…The traditional repair methods of composite materials include patch repair, scarf repair, bolt joint and so on. [8][9][10][11][12][13][14] Although these repair methods play a role in repairing the damage of composites, they also have some disadvantages. For examples, in terms of the patch repair method, the damaged material needs to be remove, and the patch is adhered to the surface of the damaged composite materials.…”

“…The traditional repair methods of composite materials include patch repair, scarf repair, bolt joint and so on 8–14 . Although these repair methods play a role in repairing the damage of composites, they also have some disadvantages.…”