Wear resistance of UHMWPE-based carbon nanocomposite subsequent AlBx ion implantation

Ultra high molecular weight polyethylene (UHMWPE) is a promising polymeric material for mechanical engineering combining such properties as low coefficient of friction, resistance to corrosive chemicals, has extremely low moisture absorption, high abrasion resistance and high impact strength. Recent large studies attempt toward improvements in tribotechnical properties of UHMWPE by adding fillers or using ion beam to modify surface of this material. In this paper wear resistance of UHMWPE composites was studied using block-on-ring test under dry sliding friction. The effects of adding carbon nano-fiber (CNF) 0.5wt% and treatment by aluminum boron (AlB_x) ion implantation onto wear resistance are reported. The main purpose was to find the rational dose and study the influence of ion dose variation onto wear of UHMWPE composite. The specimens were treated with AlB_x ion dose varied from 0.5*10¹⁷-2*10¹⁷ ion/cm². It was found that UHMWPE+CNF specimen (without ion implantation) gives high wear resistance up to 4 times and implanted specimen at ion dose of 1*10¹⁷ ion/cm² gives high wear resistance up to 3 times compare with pure UHGMWPE. Furthermore it was also shown that AlB_x ion implantation is not an effective way to increase wear resistance of UHMWPE+CNF composites which is most likely due to the influence of different thermal conductivities of the polymer matrix and carbon nano-fiber during treatment and subsequent crystallization. The thickness of the modified surface layer with a lamellar structure increased with increasing dose, reaching a maximum value of 600 microns.