Berücksichtigung vorausgegangener Ermüdungsschädigung in der Crashsimulation kurzfaserverstärkter Thermoplaste

Description

Components made of short fibre-reinforced thermoplastics are increasingly being used in vehicle design in functions where they are stressed during normal service life and where their behaviour in a crash is also important. The fatigue damage caused by repeated loading as a result of service load cases leads to a deterioration of the mechanical properties, but is not currently taken into account in crash simulation. This is where the present work comes in: it presents an approach that uses suitable experimental characterisation methods to quantify material degradation due to cyclic loading and to model its effects on crash-relevant material properties. These changed material parameters are transferred to the crash simulation depending on the prevalent damage. The necessary models are derived from observations on tensile rods and validated in bending tests on cross-ribbed beams. The presented approach shows a good predictive capability, whose discussion and outlook on further potentials represent the conclusion of the work.