Polymers are applied more and more in safety relevant parts such as bumpers and air bag covers. It has to be affirmed that they function reliably at temperatures ranging from at least -35°C to 85°C. In a crash the materials may deformed with very high strain rates going up to several 1000/s. As most of these parts are dimensioned using FEA programs reliable and realistic materials data are required. Polymers behave viscoelasticly at the applied temperatures and their properties depend on strain rate and temperature. Therefore, materials properties according to data sheets are completely inappropriate. This situation leads to the need of materials properties measured at high strain rates. In this presentation a method is shown how Young's modulus and yield point can be determined by evaluating the stress strain curve and how Young's modulus is connected to the yield stress.
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