(Prediction of Stress Relaxation Behavior of Closed-Cell Polymer foam Under Compressive Load)
Keywords:Polymer foam, Stress relaxation, Loading rate, Prediction
Recently polymer foam is mostly used in sandwich structures, an application of panel in container floors and airplane’s wings, by using the advantage of high strength to weight ratio property. In several of application difference loads are absorbed, materials can failure or unsafe to use if cannot relax old stress. The aims of this study are to study and predict the stress relaxation at various loading rates under the compressive load. The results of experiments on closed cell polyvinylchloride foam vary from 0.1 to 500 mm/min represented that difference loads effected to stress relaxation. Generalized Maxwell with Prony’s series are applied to predict stress relaxation behavior at 0.1 and 500 mm/min. The comparison results with actual test data found that both methods are indifferent and appropriate to replace the destructive method.
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