Influences of Foam Density and Core Thickness on Debond Toughness of Sandwich Specimens with PVC Foam Core

Face/core debond toughness, expressed as the critical strain energy release rate (G c ), was determined for sandwich specimens with composite and aluminum face sheets over various cross-linked PVC foam cores. Crack propagation occurred in the core, near the face/core interface for specimens with adequate face/core adhesion. Only for the highest density foam it was possible to propagate the crack in the immediate vicinity of the actual core/resin interface. The face/core debond toughness increased with increased foam density and reduced core thickness. For thick cores, the face/core toughness was independent of the core thickness.