Adhesion characterization and defect sizing of sandwich honeycomb composites

Elhadji Barra Ndiaye; Pierre Maréchal; Hugues Duflo

doi:10.1016/j.ultras.2015.05.007

Adhesion characterization and defect sizing of sandwich honeycomb composites

Ultrasonics. 2015 Sep:62:103-11. doi: 10.1016/j.ultras.2015.05.007. Epub 2015 Jun 18.

Authors

Elhadji Barra Ndiaye¹, Pierre Maréchal², Hugues Duflo²

Affiliations

¹ 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.
² Laboratoire Ondes et Milieux Complexes, Université du Havre, LOMC UMR 6294 CNRS, 75 rue Bellot, CS 80540 76058 Le Havre Cedex, France.

PMID: 26138595
DOI: 10.1016/j.ultras.2015.05.007

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.

Keywords: Bond strength evaluation; Electro-acoustic response; Sandwich honeycomb composite; Ultrasound imaging.