title: Adhesion characterization and defect sizing of sandwich honeycomb composites.
abstract: Defects may appear in composite structures during their life cycle. A 10MHz 128 elements phased array transducer was investigated to characterize join bonds and defects in sandwich honeycomb composite structures. An adequate focal law throughout the composite skin gives the ultrasonic dispersive properties of the composite skin and glue layer behind. The resulting B-scan cartographies allow characterizing locally the honeycomb adhesion. Experimental measurements are compared in good agreement with the Debye Series Method (DSM). In the processed C-scan image, flaws are detectable and measurable, localized both in the scanning plane and in the thickness of the composite skin.
authors.affiliation: Laboratoire Ondes et Milieux Complexes, Université du Havre, LOMC UMR 6294 CNRS, 75 rue Bellot, CS 80540 76058 Le Havre Cedex, France. Electronic address: elzobarz@hotmail.com.
authors.forename: Elhadji Barra
authors.initials: EB
authors.lastname: Ndiaye
authors.affiliation: Laboratoire Ondes et Milieux Complexes, Université du Havre, LOMC UMR 6294 CNRS, 75 rue Bellot, CS 80540 76058 Le Havre Cedex, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Maréchal
authors.affiliation: Laboratoire Ondes et Milieux Complexes, Université du Havre, LOMC UMR 6294 CNRS, 75 rue Bellot, CS 80540 76058 Le Havre Cedex, France.
authors.forename: Hugues
authors.initials: H
authors.lastname: Duflo
keywords: Bond strength evaluation; Electro-acoustic response; Sandwich honeycomb composite; Ultrasound imaging