Interface effect on tribological properties of titanium–titanium nitride nanolaminated structures
Résumé
anolaminated titanium]titanium nitride wTi]TiNxn structures have been deposited on silicon 100: substrates by RF reactive
sputtering in order to study their mechanical properties. Structures with graded TirTiN interface thickness of approx. 2 nm. and
with ultra-thin TirTiN interfaces approx. 0.5 nm. have been investigated with multilayer period thicknesses ranging between 20
and 2.5 nm. The deposition followed by in situ kinetic ellipsometry point out the two types of interfaces. Real period thicknesses,
measured by X-ray reflectometry, are close to the expected ones. Thin film X-ray diffraction analysis shows the polycrystalline
nature of the nanostuctures. In the superlattice, Ti and TiN individual layers are textured w002x and w111x, respectively.
Tribological tests, carried out using a CSEM pin-on-disc apparatus, point out that the wear resistance of the samples increase
when the period thickness is lowered same total thickness and growth parameters.. For small period thickness, the interface
quality has a crucial influence on the wear resistance of the samples. Best tribological properties are observed for samples with
ultra-thin interfaces and a period thickness of 2.5 nm.