Abstract
Polycrystalline TiN/NbN superiattice coatings were deposited on M2 tool steel substrates using an opposed dual-cathode unbalanced magnetron sputtering system. Superiattice deposition was achieved by placing the substrates on a cylindrical holder that rotated on an axis equidistant between, and parallel to, the faces of opposed Ti and Nb targets. Cross contamination of the targets and the alternating superiattice layers was minimized using a baffle or an extra-large cylindrical substrate holder. The superiattice period was determined by the substrate holder rotation speed. Analytical techniques including x-ray diffraction, energy-dispersive spectroscopy and transmission electron microscopy were used to characterize the structure of the superiattice coatings. Microhardness values for the superiattice coatings as high as 5200 kg/mm2 Hv0.05 have been achieved, comparable to the reported highest hardness values of single crystal TiN/VN, TiN/V0.6Nb0.4N and TiN/NbN superiattice coatings. The results indicate that the hardness of the polycrystalline TiN/NbN superiattice coatings is affected not only by superiattice period, but also by nitrogen partial pressure and ion bombardment during deposition.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1604-1609 |
| Number of pages | 6 |
| Journal | Journal of Vacuum Science and Technology A: Vacuum, Surfaces and Films |
| Volume | 10 |
| Issue number | 4 |
| DOIs | |
| State | Published - Jul 1992 |
ASJC Scopus subject areas
- Condensed Matter Physics
- Surfaces and Interfaces
- Surfaces, Coatings and Films