The Influence of Plastic Deformation on Structure of Highly Crosslinked UHMWPE Intended for Endoprosthesis Cups

Abstract:

In this paper, an attempt has been made to determine the changes in the structure of UHMWPE under the influence of deformation, which can be the cause of the decrease of functional properties. It has been found that the degree of cross-linking slightly changes due to operational loads (deformation ef=0.15-0.6). The deformation leads, however, to the systematic lowering of the degree of crystallinity and an insignificant decrease of lamella width. Tests of wide- and small-angle X-ray scattering (WAXS, SAXS) prove that this is the result of operational deformation causing a rather weak texture of crystals and the fragmentation of some lamellae. Anisotropy of the lamellar structure also takes place, which changes 2D SAXS images into ellipses with a rapidly growing axial ratio with ef value.

• Periodical: Solid State Phenomena (Volume 197)
• Pages: 13-18
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.197.13
• Online since: February 2013
• Authors: Joanna Maszybrocka, Jerzy Cybo, Jan Cwajna, Adrian Barylski, Piotr Czaja
• Keywords: Crosslinking Density, Degree of Crystallinity, Electron Beam Irradiation, Free Radical, Lamellar Structure, Oxidation, Thermal Processing, UHMWPE

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