Tribological behaviour a-C and a-C:H films doped with Ti in biological solutions

The coatings were deposited in a multi magnetron Teer sputtering device with two C targets and a Ti target in Ar atmosphere, on steel and Si substrates. To deposit hydrogenated coatings methane was introduced in the discharge atmosphere. The films were deposited in a range of 7–14 at.% Ti content. X-ray diffraction patterns revealed the presence of a nanocrystalline TiC phase. The hardness varied from 8 to 9 GPa. The tribological tests were performed under dry sliding and lubricated (0.9% NaCl water solution, physiological solution, PS, and 10% fetal bovine serum dissolved in Ringer’s saline solution, FBS) conditions, using a 100Cr6 steel balls with a diameter of 6 mm, in a pin-on-disc wear test apparatus.

► Deposition of a-C and a-C:H films doped with Ti by dc magnetron sputtering. ► Study of the interaction of a-C and a-C:H coatings in sliding contact under biological environment. ► Hydrogenated films showed better tribological performance under simulating human body fluids.