Elastomeric plateau region

FIGURE 41.8 Representative stress-strain curve for a cellular solid. The plateau region for compression in the case of elastomeric foam (a rubbery polymer) represents elastic buckling for an elastic-plastic foam (such as metallic foam), it represents plastic yield, and for an elastic-brittle foam (such as ceramic) it represents crushing. On the tension side, point A represents the transition between cell wall bending and cell wall alignment In elastomeric foam, the alignment occurs elastically, in elastic plastic foam it occurs plastically, and an elastic-brittle foam fractures at A. 

Fig. 25.11. When on elastomeric foam is compressed beyond the I inear region, the cell walls buckle elastically, giving the long plateau shown in Fig. 25.9.

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