Reduced notch sensitivity in pseudo-ductile CFRP thin ply angle-ply laminates with central 0° plies

• Published in: Composites. Part A, Applied science and manufacturing Vol. 111; pp. 62 - 72
• Main Authors: Wu, Xun, Fuller, Jonathan D., Longana, Marco L., Wisnom, Michael R.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.08.2018
• Subjects: B. Delamination; B. Fragmentation; B. Stress concentrations; C. Damage mechanics; B. Fragmentation; C. Damage mechanics; B. Stress concentrations; B. Delamination
• ISSN: 1359-835X; 1878-5840
• DOI: 10.1016/j.compositesa.2018.05.011

This paper presents an experimental investigation on the unnotched and open-hole tensile behaviour of pseudo-ductile thin ply angle-ply carbon fibre/epoxy laminates with central 0° plies. Laminates with two different configurations of [±265/0]s and [±252/0]s were designed and tested under unnotched and open-hole tensile loading. Metal-like tensile stress-strain curves with a plateau were observed in both unnotched configurations. The open-hole net-section strength of the [±252/0]s laminate attained 96% of the unnotched “yield” strength. Digital image correlation and X-ray CT-scan images showed that the same damage mechanisms of central 0° ply fragmentation and local dispersed delamination observed in unnotched pseudo-ductile laminates were present in the open-hole specimens of the same configuration. These damage mechanisms caused stress redistribution around the hole and reduced the notch sensitivity in pseudo-ductile laminates under open-hole tensile loading. The main factors governing the open-hole performance are also discussed.