Ultra high molecular weight polyethylene (UHMWPE) is actively used in various biomedical applications such as total joint arthroplasty (replacement) where it plays a role of a cartilage. One of the manufacturing techniques used to process the material is equal channel angular extrusion (ECAE). This method allows to achieve higher level of polymer molecules entanglement leading to the increased wear and oxidation resistance. Numerical modeling of the extrusion process can be used to estimate the importance of such manufacturing parameters as process temperature, extrusion rate, shape of the extrusion die, back-pressure and friction.
This research is focused on the development of high fidelity FE models of ECAE. This involves investigation of the applicability of various material constitutive models for UHMWPE and the parametric studies for the manufacturing conditions. The developed models take into account the extrusion rate, friction and temperature effects in the process and allow to obtain spatial distribution of stresses and strains in the material during and after the extrusion. FE modeling also allows to gain better understanding of the ECAE process for UHMWPE and improve the resulting mechanical and physical properties of the material.
