Tribological Properties Of Carbon Fiber Reinforced Poly-ether-ether-ketone

Ultra high molecular polyethylene (UHMWPE) has used in artificial hip, knee and other joint replacement materials for over 50 years, but in the long term clinical applications found that UHMWPE wear debris prone to induce the generation of advanced prosthesis aseptic loosening, reducing the life of artificial joints. There is an urgent need to study a new type of prosthesis material, and carbon fiber reinforced Poly-ether-ether-ketone (CF/PEEK) as an ideal alternative to artificial joint materials to superior mechanical properties, excellent wear resistance and good bio-compatibility and mechanical compatibility gradually by scientists of all ages.This paper studies biotribology performance of PEEK composites filled by carbon fiber. This paper prepares CF/PEEK composite sample of diffenent conbinations and types using compression molding in vacuum hot pressing furnace, tests the mechanical properties (wetting performance, Rockwell hardness and compression performance) of composite materials, and evaluates its molecular structure and crystallization conditions using infrared absorption spectroscopy. In addition, this paper studies the effects of adding volume of the carbon fiber, length, surface oxidation and the lubricant to PEEK and its composites tribological properties using testing machine of reciprocating friction and artificial knee joint friction, calculates coefficient and wear rate of CF/PEEK composite through the data collected in the process of friction friction, and studies the wear mechanism according to the worn surface morphology, to get the best modified parameters.Experimental results show that the degree of the improvement of CF/PEEK composite materials infiltration and adding volume of carbon fiber is related with the surface is oxidized or not, but not with the length of the carbon fiber. Carbon fiber has little effects on the hardness of CF/PEEK composite material. Infrared absorption spectra shows that, the structure of CF/PEEK composite crystal has not changed, just increases the composite crystallinity after filling and polar functional groups- carbonyl after the oxidation of carbon fibers. Adding volume of carbon fiber, length, and surface oxidation has some effects to the friction and wear properties of CF/PEEK composites, in which the most obvious impact is adding volume, followed by surface oxidation, and length is the smallest. When the adding volume of carbon fiber is 15%, the friction coefficient and wear rate is the minimum, about one-eighth of pure PEEK; The coefficient and wear rate of CF/PEEK composite after surface treatment are reduced by approximately 0.01 and 0.5; The friction and wear properties of the length of 2mm CF/PEEK composites is slightly better than the length of 1mm CF/PEEK composites. The lubrication of fetal calf serum is the most excellent, normal saline is the second and distilled water is the worst, but in the saline lubrication conditions, the friction coefficient of composite materials has the biggest changes and is unstable. CF/PEEK composites and the wear mechanism of PEEK are adhesive wear and mild abrasive wear.