This study aims to show the implementation of an optimization procedure by characterizing the material’s hyperelastic behavior in harsh environments experienced in facility testing and in real world automotive conditions. The procedure consists of conducting material tests under various simulated harsh environments, determining the co-efficients for hyperelastic material modeling and using FEA to predict and correlate the nature of failure observed in facility testing. Two commercially available and commonly employed thermoplastic elastomers (TPE), Santoprene (Ethylene-Propylene-Diene-Monomer rubber and Polypropylene blend) and Desmopan (Thermoplastic Polyurethane), were tested. The harsh environments simulated are fluid immersion tests in automobile grease. Material aging characteristics in controlled thermal conditions were also documented. Compression and tension tests were conducted in order to determine the co-oefficients of the Mooney Rivlin hyperelastic material model. Finite Element Analysis (FEA) simulations were conducted on LS-DYNA software, to determine the quasi-static stress distributions on an overslam bumper part, a typical application of automotive elastomers. Shape and topological variations were investigated in the FEA tests. It was found that certain shape and topological changes to the part result in minimizing the stress concentrations. It is hypothesized that such changes to the rubber component would result in a lower failure rate in facility testing.

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