Response of semi-crystalline thermoplastic polymers to dynamic loading: A finite element study

Mechanical behaviours and properties of polymers under dynamic loading conditions differ significantly from those under quasi-static loads. Consequently, for dynamic numerical analysis, a linear elastic/hyperelastic material model has its limitations and can produce inaccurate results. In order to obtain an adequate response to high-speed loading in simulations, a viscoelastic material model has been developed. Simulations with such a model were performed using the finite-element software Abaqus and employed to calculate the Prony series, characterising the material’s time-dependent mechanical behaviour. The initial material models, developed starting from creep and Dynamic Mechanical Analysis test data, failed to provide adequate results; hence, a customised relaxation function was suggested based on experimental tests at different strain rates. The developed material model was validated in static and dynamic simulations with good results for loads below the yield point.