Hab 2 en
Self-lubricating nanostructured coatings based on transition metal dichalcogenides alloyed with carbon
Author: Tomáš Polcar
Habilitation thesis is a review of recent results on the tribological behavior of nanocomposite coatings composed of nanoplatelets of transition metal dichalcogenides (TMD) immersed in a C-rich amorphous matrix are reviwed. It is shown that such a microstructure produces low friction coefficients under different operating conditions such as air humidity, contact pressure or temperature. Special attention is paid to the analysis of the worn surfaces after the tests by Raman spectroscopy, Auger electron spectroscopy and transmission electron microscopy. Nanoscale analysis of the wear track has revealed the formation of a thin tribolayer exclusively consisting of TMD platelets oriented to exhibit the lowest friction. In some cases, the depth reorientation of the originally randomly oriented TMD platelets as a reaction to the sliding process has been observed. This self-adaptation explains the low friction coefficient together with a high load-bearing capacity and a limited sensitivity to air humidity. Finally, future perspectives for self-lubricant nanocomposite coatings based on the TMD-C concept are presented.
- Tomáš Polcar, mailto:polcatom@fel.cvut.cz
