The University of Southampton
University of Southampton Institutional Repository

Porosity effect on residual flexural strength following low energy impact of carbon fibre composites

Porosity effect on residual flexural strength following low energy impact of carbon fibre composites
Porosity effect on residual flexural strength following low energy impact of carbon fibre composites
Studies of the combined effects of the presence of porosity (as it may result from partially effective cure cycles) and of low-energy impact damage on the residual properties of CFRP laminates have led so far to controversial results. In particular, it is not clear from the literature whether the presence of voids would blunt crack propagation following impact or rather would promote damage development. These effects would respectively either increase or reduce post-impact residual strength, relative to that of the laminate with virtually no voids, as the result of an optimal manufacturing procedure. With this in mind, different cure cycles have been applied to produce carbon fibre-reinforced polymer (CFRP) composites with various levels of void content, which were subjected to low energy impact damage (3, 4.5 and 6 J) and then to post-impact flexural strength measurement. Damage assessment using micro-focus computed tomography (μCT) was used to complement traditional ultrasonic C-scans, which proved ineffective on the high-porosity samples. Three cure-cycles were investigated: one which led to high porosity (average void content 4 vol%) and two conventional low-porosity cure cycles, only one of which included a post-cure cycle. This study has found that, despite a lower initial flexural strength, higher residual flexural strength was retained after impact in the high-porosity material than in the low-porosity one. This is explained by the lower extent of impact damage observed in the high porosity material, where voids had the effect of suppressing delamination propagation.
Carbon fibre-reinforced composites; Porosity/voids; Impact Behaviour; Post-impact flexural strength
1478-2391
205-212
Arthurs, B.
fa5b1e76-4b70-4752-a33b-6cbcf669f45e
Bull, D.J.
3569ba02-89de-4398-a14d-02c3f9b4eab2
Arumugam, V.
d42b6b9f-19e6-48b5-adde-8d271dde2eb9
Chambers, A.R.
74fa9b7e-6362-478e-a038-15f2828c5446
Santulli, C.
ec0be24d-db9f-46a6-9f41-1b89d7529212
Arthurs, B.
fa5b1e76-4b70-4752-a33b-6cbcf669f45e
Bull, D.J.
3569ba02-89de-4398-a14d-02c3f9b4eab2
Arumugam, V.
d42b6b9f-19e6-48b5-adde-8d271dde2eb9
Chambers, A.R.
74fa9b7e-6362-478e-a038-15f2828c5446
Santulli, C.
ec0be24d-db9f-46a6-9f41-1b89d7529212

Arthurs, B., Bull, D.J., Arumugam, V., Chambers, A.R. and Santulli, C. (2015) Porosity effect on residual flexural strength following low energy impact of carbon fibre composites. Polymers and Polymer Composites, 23 (4), 205-212. (doi:10.1177/096739111502300401).

Record type: Article

Abstract

Studies of the combined effects of the presence of porosity (as it may result from partially effective cure cycles) and of low-energy impact damage on the residual properties of CFRP laminates have led so far to controversial results. In particular, it is not clear from the literature whether the presence of voids would blunt crack propagation following impact or rather would promote damage development. These effects would respectively either increase or reduce post-impact residual strength, relative to that of the laminate with virtually no voids, as the result of an optimal manufacturing procedure. With this in mind, different cure cycles have been applied to produce carbon fibre-reinforced polymer (CFRP) composites with various levels of void content, which were subjected to low energy impact damage (3, 4.5 and 6 J) and then to post-impact flexural strength measurement. Damage assessment using micro-focus computed tomography (μCT) was used to complement traditional ultrasonic C-scans, which proved ineffective on the high-porosity samples. Three cure-cycles were investigated: one which led to high porosity (average void content 4 vol%) and two conventional low-porosity cure cycles, only one of which included a post-cure cycle. This study has found that, despite a lower initial flexural strength, higher residual flexural strength was retained after impact in the high-porosity material than in the low-porosity one. This is explained by the lower extent of impact damage observed in the high porosity material, where voids had the effect of suppressing delamination propagation.

Text
Porosity_effect_on_residual_flexural_strength - Version of Record
Restricted to Repository staff only
Request a copy

More information

Accepted/In Press date: 17 June 2014
e-pub ahead of print date: 1 May 2015
Keywords: Carbon fibre-reinforced composites; Porosity/voids; Impact Behaviour; Post-impact flexural strength

Identifiers

Local EPrints ID: 432508
URI: http://eprints.soton.ac.uk/id/eprint/432508
ISSN: 1478-2391
PURE UUID: 9ff9ea43-9867-47b9-98ac-24dcc0b1d409
ORCID for D.J. Bull: ORCID iD orcid.org/0000-0001-6711-6153

Catalogue record

Date deposited: 17 Jul 2019 16:30
Last modified: 27 Aug 2019 00:33

Export record

Altmetrics

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×