Damage resistance of carbon fibre reinforced epoxy laminates subjected to low velocity impact: Effects of laminate thickness and ply-stacking sequence

• Published in: Polymer testing Vol. 63; pp. 530 - 541
• Main Authors: Caminero, M.A., García-Moreno, I., Rodríguez, G.P.
• Format: Journal Article
• Language: English
• Published: Barking Elsevier Ltd 01-10-2017; Elsevier BV
• Subjects: Carbon fiber reinforced plastics; Carbon fibers; Carbon-epoxy composites; Clustering; Damage assessment; Delamination; Drop tests; Failure mechanisms; Fiber reinforced polymers; Impact damage; Impact damage resistance; Impact resistance; Impact response; Impact tests; Laminates; Photomicrographs; Ply clustering; Ply stacking; Reinforced epoxy composites; Size-scale effects; Stacking sequence; Stacking sequence (composite materials); Stiffness; Structural damage; Structural integrity; Ultrasonic testing; Velocity; Size-scale effects; Reinforced epoxy composites; Stacking sequence; Impact damage resistance; Ply clustering
• ISSN: 0142-9418; 1873-2348
• DOI: 10.1016/j.polymertesting.2017.09.016

A major concern affecting the efficient use of composite laminates is the effect of low velocity impact damage on the structural integrity [1–3]. The aim of this study is to characterize and assess the effect of laminate thickness, ply-stacking sequence and scaling technique on the damage resistance of CFRP laminates subjected to low velocity impact. Drop-weight impact tests are carried out to determine impact response. Ultrasonic C-scanning and cross-sectional micrographs are examined to assess failure mechanisms of the different configurations.
It is observed that damage resistance decreases as impact energy increases. In addition, thicker laminates show lower absorbed energy but, conversely, a more extensive delamination due to higher bending stiffness. Thinner laminates show higher failure depth. Furthermore, quasi-isotropic laminates show better performance in terms of damage resistance. Finally, the results obtained demonstrate that introducing ply clustering had a negative effect on the damage resistance and on the delamination area.