The goal of this study is to apply a heat built-up protocol on a SFRP used for structural automotive applications (PA66GF50, a polyamide filled with 50% of glass fiber in mass) to predict quickly the fatigue properties from the temperature measurements. In order to provide a relation between the full heat build-up curve and the Wöhler curve, the dissipated energy is then evaluated from the thermal measurements and the parameters of an energetic fatigue criterion are identified from the results obtained from one single sample. The fatigue curve predicted from the heat build-up curve is compared to the one obtained from a classical fatigue campaign and the agreement is very good. The energy based criterion as well as the identification of the dissipation sources from the temperature measurements are finally challenged by experimental campaigns achieved on samples, structural samples and structures.
Caractérisation rapide des propriétés en fatigue d'un polymère renforcé par des fibres courtes, pour une application automobile.