Characterization of Compressive Properties of Polymer Foam Materials Using DIC and a Modified Arcan Fixture

Abstract

AbstractA modified Arcan fixture (MAF) has been developed to characterize polymer foam materials with respect to their tensile, compressive, shear and bidirectional mechanical properties at room and at elevated temperatures. The MAF enables the realization of pure compression or high compression to shear bidirectional loading conditions that are not possible with conventional Arcan fixtures. The MAF is attached to a standard universal test machine, equiped with an environmental chamber, using specially designed grips that do not constrain the specimen wrt. rotations, and hence reduces paristic effects due to misalignment. The objective is to use digital image correlation (DIC) to obtain the unidirectional and bidirectional elastic coefficients and the stress-strain response to failure of polymer foam materials at elevated tempreature. To account for nonhomogeneity of the strain field in the specimen cross sections, a “correction factor” for the measured surface strain is determined using nonlinear finite element analysis (FEA). The paper will focus on the characterization of the compressive material properties including the MAF setup, test specimen design, experimental procedure and validated experimental results.KeywordsPVC foamModified Arcan fixtureDigital image correlationThermal degradationCompressive properties