Tribological comparative study of conventional and composite materials in biomedical applications

摘要

Ultra-High Molecular Weight Polyethylene (UHMWPE) is used as acetabular component of total hip prostheses. However, at long term, prostheses failure can occur with the increasing of wear debris. Research with composite materials is being developed for orthopaedic applications. Carbon fibre reinforced Peek (CFR Peek) is a structural composite with biomedical applications. The tribological performance of UHMWPE and 30% CFR Peek was studied against steel, under distilled water lubricated environment at 37°C. A pin-on-disk Punt-TE67 was used to evaluate the tribological performance of both materials. Accelerated test condition was used in order to perform a sliding distance equivalent to two years lifetime of a hip prostheses. A contact stress of 5 MPa and a sliding velocity of 0.5 m s were applied. Counterface roughness was measured to an arithmetic mean value Ra, of 0.05 μm. The best performance in terms of friction coefficient and wear rate was observed for CFR Peek. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) X-Ray microanalysis were used to identify the effect of test conditions on the pin's contact surface.