Impact velocity effect on the delamination of woven carbon–epoxy plates subjected to low-velocity equienergetic impact loads

• Published in: Composites science and technology Vol. 94; pp. 48 - 53
• Main Authors: Zabala, H., Aretxabaleta, L., Castillo, G., Urien, J., Aurrekoetxea, J.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 09.04.2014; Elsevier
• Subjects: Applied sciences; B. Delamination; B. Impact behaviour; C. Damage tolerance; Carbon fiber reinforced plastics; Carbon-epoxy composites; D. Ultrasonics; Damage; Delaminating; Delamination; Exact sciences and technology; Forms of application and semi-finished materials; Impact analysis; Impact loads; Impact velocity; Laminates; Polymer industry, paints, wood; Technology of polymers; D. Ultrasonics; B. Delamination; B. Impact behaviour; C. Damage tolerance; Epoxy resin; Mechanical properties; Laminated plate; Experimental study; Mineral fiber; Composite material; Impact strength; Woven material; Delamination; Fracture mode; Carbon fiber
• ISSN: 0266-3538; 1879-1050
• DOI: 10.1016/j.compscitech.2014.01.016

The low velocity impact behaviour of a woven carbon fibre/epoxy composite has been analysed in this work. The study has been divided in two experimental phases performed in a drop-weight machine. Firstly, an impact has been carried out to determine the main damage mechanisms appearing over the structure for impact energies between 1 and 20J. Force time curve patterns and three different damage inspection techniques have been employed to define an incident impact energy range (between 1.75 and 8.8J) where delamination is the main damage mode over the structure. Secondly, two impact energy levels within this range have been chosen to analyse the impact velocity effect on the generated delamination. Equienergetic impact loads, achieved with different mass and velocity combinations, have been carried out for this analysis. Results show how delaminated area can increase in a 45% while increasing impact velocity, and how this delamination growth, can lead to a 20% reduction of the residual stiffness of the structure within the analysed energy and velocity ranges.