Debonding and Kinking in Foam-Core Sandwich Beams

In this work we consider the effects of debonding in a double cantilever beam (

DCB

) specimen of aluminum faces and PVC-foam core (Divinycel H, see [

DIAB International AB, Divinycell Grade H Technical Manual, Sweden, 2003.

]), as shown in Figure 1 below. The configuration follows the one proposed by Prasad and Carlsson [

5

], which is similar to the standard ASTM D5528 94a peel test [

ASTM Standard D5528-94a. “Standard Test Method for Mode-I Interlaminar Fracture Toughness of Unidirectional Fiber-Reinforced Polymer Matrix Composites,” ASTM Annual Book of ASTM Standard 15.03, 283–292, American Society for Testing and Materials, 1999.

]. All materials are linear elastic, and four cases of core density are considered (H 60, H 80, H 100, and H 250), which have been the subject of other investigations [e.g.,

Shivakumar, K., Chen, H., and Smith, A. S., Journal of Sandwich Structures and Materials vol. 7, 77–90, 2005.

] too. All cases are typical of foam-core sandwich structures, where the core is much more flexible than the adhesive and faces. In each case debonding is introduced between the core and adhesive at the loaded end.