Ti–B and Ti–B–C coatings deposited by plasma immersion ion implantation and their fretting behavior

Ti–B and Ti–B–C coatings were deposited by a two-step plasma immersion ion implantation (PIII) process. A structural study revealed that as-deposited PIII Ti–B coatings are amorphous and did not crystallize on vacuum annealing up to 800 °C. The coefficient of friction and the wear rate of such as-deposited and annealed PIII Ti–B coatings sliding against corundum under non-lubricated conditions were found to be higher than the ones for crystalline TiB2 coatings deposited by PVD. Attempts to decrease friction and wear rate resulted in depositing PIII Ti–B based coatings in a methane atmosphere. Such PIII Ti–B–C coatings contain both hard TiB2 and lubricating DLC phases. They show in non-lubricated fretting test conditions, a low coefficient of friction and a good wear resistance in comparison to industrial currently available PVD TiB2 and PVD TiN coatings.