Creep is one of the main time-dependent properties of polymeric materials, due to which strain under load increases with time. When unloaded, material gradually returns to its original form. Under dynamic load, the process of reformation between cycles is not fast enough and strain starts to accumulate. Tests were made with polyether ether ketone (PEEK) samples with three different temperatures and frequencies. We analyzed the influence of temperature, frequency and stress amplitude on strain accumulation. We also observed the impact of different test conditions on viscous and elastic part of strain.
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