Crushing behaviour of cellular cordierite foams

The compressive behaviour of cordierite foams fabricated by the polymer foam replication process was studied at room temperature using a compliant polymeric layer (2 mm thickness PVC) to assist in uniformly loading these brittle foams. Image analysis was used to characterise the microstructure of the samples and provided a basis for evaluating the compressive behaviour of the foams. The cordierite foams were found to exhibit the classical three region characteristic stress-strain behaviour of brittle foams and typical compressive strength ultimate values for isotropic open cellular foams (2-7 MPa). These foams appeared to fail by a damage accumulation process rather than by catastrophic collapse of a bard of cells perpendicular to the loading direction. Evidence suggests that there seems to be a close relationship between the crushing strength of the bulk foam and the microstructure of these ceramic foams.