Damage detection and self-repair in hollow glass fiber fabric-reinforced epoxy composites via fiber filling

Abstract

2Hollow glass fiber reinforced epoxy matrix composites were produced to study whether the damage development can be followed and the self-repair can triggered by filling the fibers with suitable additives. Composite plates were manufactured by the hand layup and vacuum assisted resin transfer molding techniques. To detect subcritical transverse impact damage, hollow fibers were filled with an ultraviolet fluorescent dye, whereas for selfrepair, they were filled with a polyester resin along with the corresponding accelerator. The healing process was induced at different temperatures and continued for different durations. It was demonstrated that the targeted damage detection and self-repair can be achieved using thin (10-13 µm outer diameter) reinforcing hollow fibers. The selfrepairing ability was demonstrated in three point bending tests and the healing was confirmed by inspection with scanning electron microscopy.

Recent advances in fiber/matrix interphase engineering for polymer composites

“…In the latter case the stoichiometric ratio should be considered by different amount or sizes of the related capsules to be deposited, which is a quite hard task. Due to this reasons the single capsule technique has certainly more chance to a successful application since these capsules may be added through a carrier resins that could be in principle different from the composite matrix [141]. To trigger the polymerization of such "matrix dissimilar" resins additional treatments (heating, UV or electron beam indication) may be needed.…”

New method for determining the bending modulus of solid and hollow fibers from deflection tests

“…Ωx,i and Ωy,i determined for the xi and yi coordinates of each Pi are not averaged, but the individual Ex,i és Ey,I values are calculated with the corresponding CEi and averaged according to Equation (21). (20) Alternative to the average point method, the reciprocals of the Ω parameters calculated from the individual coordinates of the end-points are averaged here.…”

“…Fibre deflection tests were performed on solid and hollow glass fibres of 50 mm length earlier and evaluated using only the vertical displacements of the fibre ends. Results of these tests were reported earlier in [18], [21] and [23]. The essence of this method is that a fibre is clamped horizontally at one end ( Figure 1) and a vertical measuring scale is used to read the vertical displacement (fB=-yB) of the free fibre end with 0.5 mm precision.…”

‘Containers’ for self-healing epoxy composites and coating: Trends and advances

“…It was found that the presence of HGF within a CFRP laminate produce minimal degradation in flexural strength and ply disruption. Recently, much thinner hollow glass fibers (13 !m outer diameter) were used in a damage-detecting and self-repairing epoxy composite to ensure major reinforcement [67]. Self-repair in this system was achieved by adding polyester resin (catalyzed resin and initiator) to the hollow fibers.…”