Long term creep behavior of a short carbon fiber reinforced peek at high temperature
Résumé
Short carbon fiber reinforced high performance thermoplastics, like poly (ether ether ketone) (PEEK), are materials very interesting for high temperature application. However, long term creep behaviour of this kind of material is still ill known. In this study, both quasi-static and dynamic mechanical testing are used to characterized short term and long term creep respectively at 150°C. The material is shown to behave linear viscoelastically for stresses below its elastic limit. Then a linear viscoelastic model is identified. Long term creep compliance is obtained via the time temperature superposition principle (TTSP) and well described with a Prony series. Moreover, this method allows effect of temperature and ageing determination. Nevertheless, the model underestimates viscoelastic strain if used to simulate multi steps creep/recovery tests.