LONG-TERM PERFORMANCE OF CONTINUOUS FIBER REINFORCED THERMOPLASTIC COMPOSITES

Pure and fiber-reinforced thermoplastic polymers are prone to failure under creep loading due to high molecular mobility they possess, which renders lifetime prediction under creep loading crucial. Pure and short fiber-reinforced composites were shown to exhibit two main stress-dependent failure mechanisms depending on the magnitude of creep stress applied: plasticity-controlled and crack growth controlled failure mechanisms, which can be identified by comparing the lifetimes in static and cyclic fatigue at equal value of maximum stress [1]. In this work, the same procedure is applied to transversely loaded unidirectional (UD) composites for identification of failure mechanisms to develop lifetime prediction models and acceleration methods based on them. Plasticity controlled failure mechanism was observed for continuous fiber-reinforced UD composites as well.