Evaluation of mode III interlaminar fracture toughness of laminated composites

Shinji Ogihara, Katsuhiro Matsuda

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Mode III interlaminar fracture toughness in CFRP is evaluated experimentally by•• using the Edge Crack Torsion (ECT) test. A material system used is T700S/2500 carbon/epoxy system. Laminate configuration is [90/(+45/-45)3/(-45/+45)3/90]s with a delamination introduced by a 25μm-thick kapton film at the mid-plane along one edge. The specimen size is 90mm long, 40mm wide and 4.2mm thick. The film lengths were 0, 5, 10 and 15 mm. A natural crack is produced with a wedge from the film edge. The resulting crack lengths are from 8mm to 18mm. Two data reduction methods are used to calculate mode III interlaminar fracture toughness GIIIC at the maximum load and load at onset of nonlinearity. Soft X-ray radiograph is used to observe delamination propagation. Three-dimensional finite element analysis is performed to calculate the distribution of mode I, mode II, and mode III energy release rate along the delamination front. The validity of the experimental method is also discussed.

Original languageEnglish
Title of host publicationProceedings of the 16th International Conference on Composite Materials, ICCM-16 - "A Giant Step Towards Environmental Awareness
Subtitle of host publicationFrom Green Composites to Aerospace"
Publication statusPublished - 1 Dec 2007
Event16th International Conference on Composite Materials, ICCM-16 - "A Giant Step Towards Environmental Awareness: From Green Composites to Aerospace" - Kyoto, Japan
Duration: 8 Jul 200713 Jul 2007

Publication series

NameICCM International Conferences on Composite Materials

Conference

Conference16th International Conference on Composite Materials, ICCM-16 - "A Giant Step Towards Environmental Awareness: From Green Composites to Aerospace"
CountryJapan
CityKyoto
Period8/07/0713/07/07

Keywords

  • CFRP
  • Delamination
  • Energy release rate
  • Mode III interlaminar fracture toughness

Cite this

Ogihara, S., & Matsuda, K. (2007). Evaluation of mode III interlaminar fracture toughness of laminated composites. In Proceedings of the 16th International Conference on Composite Materials, ICCM-16 - "A Giant Step Towards Environmental Awareness: From Green Composites to Aerospace" (ICCM International Conferences on Composite Materials).