Tailored synthesis of TiC/a-C nanocomposite tribological coatings
Author/s
Martínez-Martínez, D.; López-Cartes, C.; Justo, A.; Fernández, A.; Sánchez-López, J.C.; [et al.]Date
2005-10-25Keywords
Nanocomposite coatings
TiC - amorphous C coatings
Magnetron Sputtering PVD
Microstructure
Pin on disc wear testing
Tribology
Abstract
Composite coatings made of nanocrystalline TiC (nc-TiC) particles and amorphous carbon (a-C) have been prepared in a double magnetron sputtering system using graphite and titanium targets under Ar bombardment. Chemical composition and microstructure of coatings were studied by transmission electron microscopy (TEM), electron energy loss spectroscopy (EELS), and x-ray diffraction (XRD) for a set of samples prepared varying the ratio and intensity of power applied to each magnetron. Changes in coatings microstructure, from a quasipolycrystalline TiC to a nanocomposite formed by nanocrystals of TiC embedded in an amorphous matrix of carbon (nc-TiC/a-C), are observed depending on the synthesis conditions.
Tribological and mechanical properties of coatings were tested using a pin-on-disk tribometer and an ultramicrohardness indenter, respectively. Coatings with moderate hardness (7-27 GPa), low friction (0.1-0.2), and low wear rates (k similar to 10(-7) mm(3)/N m) were obtained. A percentage ...
Type
article