The Tribological Properties of the DLC Coatings Sliding Against Al_2O_3 Counterbody

10.6567/IFToMM.14TH.WC.PS18.005

W. H. Kao；Y. T. Hsieh

Pulsed-DC ； Tribological behaviour ； Hertzian pressure

Proceedings of the 14th IFToMM World Congress

14th-5（2015 / 11 / 06）

504 - 509

英文

In theory, diamond-like carbon coatings (DLC) possess high fatigue life, high hardness, high chemical inertness, low friction and high wear resistance. Those properties of DLC coatings depend on the deposition method and applied conditions. However, the effects on the coating properties of the pulsed-DC power frequency used in the deposition process have received comparatively little attention. Accordingly, in this study the gradient coating design of amorphous hydrogenated diamond-like carbon with doped Zr metal (DLC-x) deposited onto the interlayer Zr/a-C:Zr, and then Zr/a-C:Zr/DLC-x coatings are deposited on substrate AISI M2 steel disks using a closed field unbalanced magnetron (CFUBM) sputtering system with pulsed-DC power frequencies in the range 30 kHz to 110 kHz (the x in the term DLC-x is the power frequencies in the deposition process). The study investigates the tribological properties of the Zr/a-C:Zr/DLC-x coatings under ball-on-disk point contact wear mode using an oscillation friction and wear tester. The tribological behaviour was discussed based on hardness (H), elastic modulus (E), adhesion property, initial Hertzian pressure and transferred layer on contact surfaces of wear pairs. The experimental results display the DLC-110 coating with the good adhesion property, the lowest initial Hertzian pressure and the lowest friction coefficient possesses excellent wear resistance.