Unification of strength scaling between unidirectional, quasi-isotropic, and notched carbon/epoxy laminates

Xu, Xiaodong; Wisnom, Michael R.; Chang, Kuan; Hallett, Stephen R.

Abstract

An investigation into size effects and notch sensitivity in quasi-isotropic carbon/epoxy laminates was carried out. The purpose is to draw a complete picture of the strength scaling in unidirectional, quasi-isotropic, and notched carbon/epoxy laminates. A link was established between the strength scaling of the unidirectional and quasi-isotropic laminates. Efforts were made to understand the relationship between unnotched and open-hole strengths. For very small holes, the notched strengths approach the unnotched strength limit. A scaling law based on Weibull statistics was used to predict the unnotched laminate strengths. For very large holes, the same scaling law in conjunction with a detailed 3D ply-by-ply FE analysis with matrix cracks in the 90° plies and delamination cohesive interface elements was used to predict the large notched strengths. A good agreement between the modelling and experimental results was achieved. The effects of 90° matrix cracks on unnotched and notched strengths were also studied.

• Journal Article Type: Article
• Acceptance Date: Jul 22, 2016
• Online Publication Date: Jul 25, 2016
• Publication Date: Nov 1, 2016
• Deposit Date: Feb 15, 2021
• Publicly Available Date: Feb 17, 2021
• Journal: Composites Part A: Applied Science and Manufacturing
• Print ISSN: 1359-835X
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 90
• Pages: 296-305
• DOI: https://doi.org/10.1016/j.compositesa.2016.07.019
• Keywords: A. Laminates; B. Strength; B. Stress concentrations; Scaling
• Public URL: https://uwe-repository.worktribe.com/output/7094482
• Additional Information: This article is maintained by: Elsevier; Article Title: Unification of strength scaling between unidirectional, quasi-isotropic, and notched carbon/epoxy laminates; Journal Title: Composites Part A: Applied Science and Manufacturing; CrossRef DOI link to publisher maintained version: https://doi.org/10.1016/j.compositesa.2016.07.019; Content Type: article; Copyright: © 2016 Elsevier Ltd. All rights reserved.