The influence of surface roughness on friction and wear of machine element coatings

• The use of low frictioncoatings like amorphous carbon or metal-doped carbon coatings on machineelements is constantly increasing. Most often, a surface treatment, e.g. grinding and polishing or honing, is required for optimal performance of the coated machineelement. This can be time consuming and costly. In this study, the effect of surfaceroughness on friction and sliding wear of two different coatings, one tungsten containing and one chromium containing coating, were examined using a ball-on-disc test. Ball bearing steel plates were grinded to different surfaceroughnesses and coated with the two different coatings. The friction was found to depend on surfaceroughness where the rougher surfaces gave higher friction coefficients. The wear rate for the a-C:W coating was found to be independent of the roughness, whereas the roughness had a strong influence on the wear rate for the a-C:Cr coating. This could partly be explained by a difference in wear mechanism, where fatigue wear was observed for the a-C:Cr coating but not for the a-C:W coating.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Materialteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Materials Engineering (hsv//eng)

Publication and Content Type

ref (subject category)

art (subject category)