AbstractThe fracture behavior of rigid polyurethane foams has been investigated and is shown to obey the Griffith criterion for fracture in so far as the predicted behavior of tensile strength on the size of artificially introduced cracks is concerned. The energy for crack propagation (fracture surface energy) has been measured as 91.4J/m2. From this result, the intrinsic flaw size of the material is calculated. This value was found to be within the range of cell dimensions of the material.
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