Adaptive VN/Ag nanocomposite coatings with lubricious behavior from 25 to 1000 °c
AuthorAouadi, S. M.
Singh, D. P.
Stone, D. S.
Voevodin, A. A.
Google Scholar check
MetadataShow full item record
A two-phase nanocomposite coating that consists of inclusions of silver in a vanadium nitride matrix (VN/Ag) was investigated as a potential adaptive coating with a reduced friction coefficient from 25 to 1000 °C. This nanocomposite structure was selected based on the premise that silver and silver vanadate phases would form on the surface of these coatings, reducing their friction coefficient in the (i) room to mid-range and (ii) mid-range to high temperatures, respectively. Silver and vanadium were expected to react with oxygen at high temperatures and create a lubricious silver vanadate film on the coating. The VN/Ag coatings were deposited using unbalanced magnetron sputtering and their elemental composition was evaluated using X-ray photoelectron spectroscopy. The tribological properties of the materials against Si 3N4 balls were investigated at different temperatures. The lowest friction coefficients recorded for samples with identical compositions were 0.35, 0.30, 0.10 and 0.20 at 25, 350, 700 and 1000 °C, respectively. Post-wear testing Raman spectroscopy and X-ray diffraction (XRD) measurements revealed the formation of silver vanadate compounds on the surface of these coatings. In addition, real time Raman spectroscopy and high temperature XRD revealed that silver vanadate, vanadium oxide and elemental silver formed on the surface of these coatings upon heating to 1000 °C. Upon cooling, silver and vanadium oxide were found to combine at about 400 °C, leading predominantly to the formation of silver vanadate phases on the surface of these materials. © 2010 Acta Materialia Inc. Published by Elsevier Ltd.
Showing items related by title, author, creator and subject.
Fabrication, characterization, and evaluation in drug release properties of magnetoactive poly(ethylene oxide)-poly(l -lactide) electrospun membranes Savva, I.; Odysseos, A. D.; Evaggelou, L.; Marinica, O.; Vasile, E.; Vekas, L.; Sarigiannis, Y.; Krasia-Christoforou, T. (2013)The fabrication of electrospun magnetoactive fibrous nanocomposite membranes based on the water-soluble and biocompatible poly(ethylene oxide) (PEO), the biocompatible and biodegradable poly(l-lactide) (PLLA) and preformed ...
Microstructure and nanomechanical properties of pulsed excimer laser deposited DLC:Ag films: Enhanced nanotribological response Constantinou, M.; Pervolaraki, M.; Nikolaou, P.; Prouskas, C.; Patsalas, P.; Kelires, P.; Giapintzakis, John; Constantinides, G. (2017)Diamond-like carbon:silver (DLC:Ag) thin films, with metal contents as high as 16.8 at.%, have been deposited on silicon substrates using pulsed excimer laser deposition
Fabrication and characterization of superparamagnetic and thermoresponsive hydrogels based on oleic-acid-coated Fe3O4 nanoparticles, hexa(ethylene glycol) methyl ether methacrylate and 2-(acetoacetoxy)ethyl methacrylate Papaphilippou, P.; Pourgouris, A.; Marinica, O.; Taculescu, A.; Athanasopoulos, G. I.; Vekas, L.; Krasia-Christoforou, T. (2011)Stimuli-responsive hydrogel nanocomposites comprised of swollen polymer networks, in which magnetic nanoparticles are embedded, are a relatively new class of "smart" soft materials presenting a significant impact on various ...