A constitutive model for polyether ether ketone (PEEK) in various mechanical states

Polyether ether ketone (PEEK) with its excellent performances is widely used in advanced machinery, nuclear engineering, aviation, aerospace and other scientific & technological fields. In order to describe the mechanical behaviors of PEEK in view of coupled effects of strain, strain rate and temperature, based on the famous JC (Johnson-Cook) constitutive model, a piecewise JC constitutive model was established for PEEK in 3 mechanical states at different temperatures. Compared with the traditional JC model and a modified one in previous literatures, the proposed piecewise JC constitutive model can better predict the flow behaviors of PEEK at high temperatures. It provides a theoretical foundation for the numerical simulation and engineering application of PEEK in composites in the future.