Compressed open-cell solid foams frequently exhibit spatially inhomogeneous distributions of local stretch. The theoretical aspects of this deformation habit have not been clearly elucidated. Here we briefly discuss the energetics of the problem to show that the stretch inhomogeneity stems from the nonconvexity of the underlying potential. We also perform displacement field measurements using the Digital Image Correlation technique, and discuss the results in light of the theory. [S0094-4289(00)01904-6]

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