Free edge effects study in laminated composites using Digital Image Correlation: effect of material and geometrical singularities

P. Lecomte; B. Paluch; M. Brieu

doi:10.1051/epjconf/20100620011

EPJ

Free edge effects study in laminated composites using Digital Image Correlation: effect of material and geometrical singularities

P. Lecomte¹, B. Paluch² and M. Brieu¹

¹ EC-Lille, LML, Boulevard Paul Langevin, Cité Scientifique, 59655 Villeneuve d'Ascq France
² ONERA-Lille, DADS-CRD, 5 boulevard Paul Painlevé 59045 Lille Cedex France

Abstract

Composite materials are today used for various industrial applications. However, delamination on free edges, where stress gradients are strong, still remain a problem. In the aim of a better understanding of such phenomenons, Digital Image Correlation (DIC) measurements have been carried out on [(15_n/-15_n)₂]_s laminates under uniaxial tensile strain. Three different composites with different mechanical properties and microstructure have been tested as well as two samples geometries: flat and with ply drop. Experimental results show high shear strain concentrations near 15°/-15° interlaminar interfaces on free edges which depend on material mechanical properties and microstructure and increase in the vicinity of a geometrical singularity.