INVESTIGADORES
FRONTINI patricia Maria
congresos y reuniones científicas
Título:
MECHANICS OF POLYPROPYLENE UNDER IMPACT LOADING
Autor/es:
JUAN P TORRES; PATRICIA FRONTINI; MARTÍN MACHADO; ZOLTAN MAJOR
Reunión:
Conferencia; 17 th conference on Experimental Mechanics; 2016
Resumen:
Polypropylene (PP) is a semi-crystalline polymer widely used in automotive componentsthat may be subjected to accidental impact or crash loading. In this work, we investigate thethermomechanical behaviour of PP under dynamic loading both experimentally and analytically.To this end, we carried out high strain-rate tensile tests using digital image correlation(DIC) to measure full 2D strain fields, and infrared thermography to determine specimentemperature rise. The results were used to calibrate an advanced 3D thermomechanical constitutivemodel that accounts for the pressure, strain-rate and temperature dependence of PPdynamic response at large strains. We evaluated the predictability of this model by runningfinite element (FEA) simulations of the falling weight biaxial impact tests (FWT) and comparingthe predictions with experimental force-time curves. A critical feature of PP is it undergoesa ductile-brittle transition at moderate deformation rates and ambient tempera-ture.An assessment of the FEA computed stress-strain fields developed in the FWT samples allowedus to propose invariant-based failure criteria to predict the onset of both ductile andbrittle failure.