Tribological Properties of CoCrMo Alloy Surface-Modified by Laser Texturing and with Diamond-Like-Carbon Coating

The laser-textured surfaces of CoCrMo alloy,an advanced artificial human joint material,were further modified with diamond-like-carbon(DLC) coatings,synthesized by close field unbalanced magnetron sputtering ion plating.The friction-coefficient and wear-resistance of the mating-pair,comprising the control and DLC-coated CoCrMo samples and ultra-high molecular weight polyethylene(UHMWPE),were investigated with scanning electron microscopy and energy dispersive spectroscopy in BSA solution and normal saline,respectively.The preliminary results show that the modification by laser-texturing and DLC-coating had a major impact.For example,the DLC-coated CoCrMo/UHMWPE pair had much higher friction-coefficient,significantly lower wear-rate(or stronger wear-resistance),considerably fewer sticky UHMWPE-debris and sizable shallower wear-tracks than the bare CoCrMo/UHMWPE pair.In addition,the UHMWPE wear-debris was found to be good self-lubricant for the DLC-coated CoCrMo/UHMWPE pair.