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arXiv · 1202.3234

First principles study of water-based self-assembled nanobearing effect in CrN/TiN multilayer coatings

David Holec·Jörg Paulitsch·Paul H. Mayrhofer
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Abstract

Recently, we have reported on low friction CrN/TiN coatings deposited using a hybrid sputtering technique. These multilayers exhibit friction coefficients $\mu$ below 0.1 when tested in atmosphere with a relative humidity $\approx25%$, but $\mu$ ranges between 0.6-0.8 upon decreasing the humidity below 5%. Here we use first principle calculations to study O and H adatom energetics on TiN and CrN (001) surfaces. The diffusional barrier of H on TiN(001) is about half of the value on CrN(001) surface, while both elements are stronger bonded on CrN. Based on these results we propose a mechanism for a water-based self-assembled nanobearing.

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David Holec, Jörg Paulitsch, Paul H. Mayrhofer. 2012-02-15. First principles study of water-based self-assembled nanobearing effect in CrN/TiN multilayer coatings. https://arxiv.org/abs/1202.3234

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