Numerical simulation of low-velocity impact loading of a ductile polymer material

摘要

Mechanical impact loading of injection-moulded components was simulated. The material was a talc filled and elastomer-modified polypropylene used in automotive exterior parts. The material model was the linear-elastic-viscoplastic SAMP-1 model, which features pressure-dependent yield stress, plas tic dilatation and a simple damage model. The model was calibrated with data from tests in uniaxial ten sion, shear and uniaxial compression, utilising 3D digital image correlation for full-field displacement measurements. With the calibrated model, two load cases were simulated; centrally loaded clamped plates and three-point bending of bars. The predictions of force vs. deflection were good to fair. The results are discussed in terms of deficiencies of the calibration data, heterogeneity and anisotropy of injection-moulded components, and shortcomings of the model. In particular, the hardening curves at high strain rates are uncertain, and tests in biaxial tension would be useful.