Friction anisotropy: A unique and intrinsic property of decagonal quasicrystals

TitleFriction anisotropy: A unique and intrinsic property of decagonal quasicrystals
Publication TypeJournal Article
Year of Publication2008
AuthorsPark JY, Ogletree DF, Salmeron M, Jenks CJ, Thiel PA, Brenner J, Dubois JM
Journal TitleJournal of Materials Research
Date PublishedMay
Type of ArticleArticle
ISBN Number0884-2914
Accession NumberISI:000255543800038
Keywordscoatings, microscopy, SURFACE OXIDATION

We show that friction anisotropy is an intrinsic property of the atomic structure of Al-Ni-Co decagonal quasicrystals and not only of clean and well-ordered surfaces that can be prepared in vacuum [J.Y. Park et al., Science 309, 1354 (2005)]. Friction anisotropy is manifested in both nanometer-size contacts obtained with sharp atomic force microscope tips and macroscopic contacts produced in pin-on-disk tribometers. We show that the friction anisotropy, which is not observed when an amorphous oxide film covers the surface, is recovered when the film is removed due to wear. Equally important is the loss of the friction anisotropy when the quasicrystalline order is destroyed due to cumulative wear. These results reveal the intimate connection between the mechanical properties of these materials and their peculiar atomic structure.

Alternate JournalJ. Mater. Res.