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thermally activated healing in a mendable resin using a non woven emaa fabric

journal contribution
posted on 01.02.2012, 00:00 authored by Russell VarleyRussell Varley, G P Parn
This paper explores the efficacy of polyethylene-co-ethacrylic acid (EMAA), as a thermally activated thermoplastic healing agent embedded within a carbon fibre reinforced epoxy composite. EMAA fibres have been shown to effectively restore mode I properties in a fibre reinforced composite after thermal activation yet other forms of the healing agent or modes of deformation have so far not been studied at all. This work, uses EMAA in the form of a non-woven mesh, rather than a woven fabric to study the healing mechanism and effectiveness of property restoration for mode I (crack opening) and mode II (shear) failure as well as for high speed impact. Property restoration after mode I damage was found to be over 200% and increased with increasing EMAA concentration. For mode II shear failure, the property restoration was reduced to a little over 100% regardless of EMAA concentration. Mode II analysis also showed that the modulus could be restored to about 80% of its original value when
modified with EMAA. Repeated impacting using a falling weight test produced no property restoration after healing, yet the modified laminates appeared protected from further damage compared with an unmodified laminate. This was attributed to the formation of a ductile thermoplastic layer mitigating further damage. Scanning electron microscopy revealed that regardless of the extent of healing, the form of the healing agent or the mode of damage, the unique pressure delivery mechanism previously identified, was always observed to occur.

History

Journal

Composites Science and Technology

Volume

72

Issue

3

Pagination

453 - 460

Publisher

Elsevier

Location

Amsterdam, The Netherlands

ISSN

0266-3538

Language

eng

Publication classification

C1.1 Refereed article in a scholarly journal

Copyright notice

2011, Elsevier