An experimental study of scaling effects in notched quasi-isotropic carbon/epoxy laminates under compressive loads

Xu, Xiaodong; Paul, Aakash; Sun, Xiaoyang; Wisnom, Michael R.

Abstract

The size effects in centre-notched quasi-isotropic carbon/epoxy laminates under compression were investigated. The in-plane dimensions of the baseline specimen were scaled up by a factor of up to 14. The centre-notched specimens were compared to open-hole specimens of the same dimensions. It was found that compressive strength of the small centre-notched specimen is similar to that of the open-hole specimen. However, as the in-plane dimensions increase, the centre notches are weaker than the open holes, and start to follow a Linear Elastic Fracture Mechanics (LEFM) scaling line. These trends were well captured by a Composite Compressive Strength Modeller (CCSM) using the fracture toughness measured in the current study. Fibre micro-buckling was confirmed to be the dominant failure mechanism under compression. The failure mechanisms under compression were also compared against those under tension. Matrix splitting under compression was observed through X-ray Computed Tomography but was less extensive than under tensile loading.

• Journal Article Type: Article
• Acceptance Date: Jun 23, 2020
• Online Publication Date: Jul 2, 2020
• Publication Date: Oct 1, 2020
• Deposit Date: Feb 15, 2021
• Publicly Available Date: Jul 3, 2021
• Journal: Composites Part A: Applied Science and Manufacturing
• Print ISSN: 1359-835X
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 137
• Article Number: 106029
• DOI: https://doi.org/10.1016/j.compositesa.2020.106029
• Keywords: Mechanics of Materials; Ceramics and Composites
• Public URL: https://uwe-repository.worktribe.com/output/7094439
• Additional Information: This article is maintained by: Elsevier; Article Title: An experimental study of scaling effects in notched quasi-isotropic carbon/epoxy laminates under compressive loads; Journal Title: Composites Part A: Applied Science and Manufacturing; CrossRef DOI link to publisher maintained version: https://doi.org/10.1016/j.compositesa.2020.106029; Content Type: article; Copyright: © 2020 Elsevier Ltd. All rights reserved.