Fretting wear behavior of PVD TiB2 coatings

TiB2 coatings deposited on hardened high-speed steel by magnetron sputtering were tested for their friction and wear behavior. Fretting wear tests (mode I) were carried out on as-deposited coatings, and after annealing in air at 600 °C for 1 h. The as-deposited magnetron sputtered TiB2 coating shows a better wear resistance (2000 μm3/J) than a hard TiN coating. On the contrary, the annealed TiB2 coating shows a low wear resistance (14 000 μm3/J) due to intensive cracking and oxidation. However, a low coefficient of friction was not noticed with neither as-deposited nor annealed TiB2 coatings.