PROPERTIES OF CrN AND CrN/DLC COATINGS IN TRIBOLOGICAL SYSTEMS LUBRICATED WITH ARTIFICIAL SALIVA

The paper investigates the effect of CrN and CrN/DLC coatings deposited using the PACVD technique on the tribological and mechanical properties of 316L stainless steel. The hardness of the coatings and 316L steel was determined using the instrumental indentation method. Tribological tests were performed on a TRB3 tribometer in a rotating ball-on-disc configuration. Al2O3 balls were used as countersamples. The tests were performed under dry friction conditions and under lubrication with artificial saliva at pH 5.2 at a temperature of 39C simulating inflammation. A scanning microscope was used to measure the thickness of the coatings, and a confocal microscope was used to study the geometric structure of the surface before and after the tribological tests. The wetting angle was measured using an optical tensiometer. The use of CrN and CrN/ DLC coatings reduced the coefficient of friction by 10% and 85%, respectively, for technically dry friction and by 44% and 82% for friction with artificial saliva lubrication. The test results indicate good cooperation of the CrN and CrN/DLC coatings with the lubricant used