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Fuller, Marina L. Suominen; Fernández, Luis Rodríguez; Massoumi, G.R.; Lennard, W. N.; Kasrai, M.; Bancroft, G.M.

doi:10.1023/a:1019195404055

Cited by 96 publications

(20 citation statements)

References 26 publications

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“…The film thickness can be calculated from the XANES spectra at the phosphorus K-edge according to a method described elsewhere [51]. A linear relationship was found between the height of the phosphate peak on the P K-edge FY spectra and the phosphorus areal density obtained from particle induced X-ray emission (PIXE) elemental analysis technique assuming that zinc pyrophosphate (Zn 2 P 2 O 7 ) with a density of 3.75 g/cm )3 is exclusively formed.…”

Section: Phosphorus K-edge Xanesmentioning

confidence: 99%

“…A linear relationship was found between the height of the phosphate peak on the P K-edge FY spectra and the phosphorus areal density obtained from particle induced X-ray emission (PIXE) elemental analysis technique assuming that zinc pyrophosphate (Zn 2 P 2 O 7 ) with a density of 3.75 g/cm )3 is exclusively formed. Using the described method [51], the average film thickness was found to range between 40 and 225 nm. The thickness was found to generally increase with concentration.…”

Section: Phosphorus K-edge Xanesmentioning

confidence: 99%

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Chemical characterization and nanomechanical properties of antiwear films fabricated from ZDDP on a near hypereutectic Al–Si alloy

et al. 2005

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X-ray absorption near edge structure (XANES) spectroscopy was used to monitor the products formed during the breakdown of the engine additive ZDDP during its action as a protective tribochemical agent. This investigation examines the film formed under various physical conditions on a near hypereutectic Al-Si alloy. For the first time, tribochemical films (tribofilms) formed on a high silicon weight content alloy, with virtually no ferrous component have been studied. Phosphorus K-and L-edge spectroscopies show that under typical engine operating conditions, the tribofilms have similar chemical composition over a range of different test conditions. X-ray photoelectron emission microscopy (X-PEEM) reveals that the polyphosphate glasses formed vary in chain length within localized regions. The mechanical properties of the substrate and the tribofilms were acquired using a Triboscope Ò from Hysitron Inc. The elastic moduli can be extracted from the indentation curves and show that the tribofilms' mechanical properties are similar to those of the tribofilms which form on steel under similar conditions.

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Section: Phosphorus K-edge Xanesmentioning

confidence: 99%

Section: Phosphorus K-edge Xanesmentioning

confidence: 99%

Chemical characterization and nanomechanical properties of antiwear films fabricated from ZDDP on a near hypereutectic Al–Si alloy

et al. 2005

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“…The film thickness can be roughly estimated by adding the stopping power of each possible element of the film and assuming (1) a film density of 3.75 g/cm 3 [25]; (2) the compositions of AW films formed by ZDDP-containing oil and FF oil are the same, and (3), the films are uniform. The calculated values of the film thickness formed in ZDDPcontaining oil and FF oil are *48 nm and *19 nm, respectively.…”

Section: Worn Depth and Volumetric Wear Ratesmentioning

confidence: 99%

A Novel Method for Quantitative Determination of Ultra-low Wear Rates of Materials, Part I: On Steels

Shakhvorostov

Pereira

et al. 2008

Tribol Lett

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A novel method for the quantitative determination of the wear of materials at very low wear rates is introduced here. The main concept involves implanting gold as a trace marker into the tested materials, and measuring the gold concentration and depth profile before and after the wear tests by Rutherford backscattering (RBS). The amount of gold loss is related to the material loss under the tested conditions. The background concentration of gold in AISI 1095 and 52100 steels has been determined by neutron activation analysis (NAA; *3 and 33 wt. ppb, respectively). Several fluences (1 9 10 15 -1 9 10 16 atoms/ cm 2 ) of gold were implanted into AISI 52100 steel samples in order to evaluate the changes in the mechanical and tribological properties induced by implantation. The new method shows the relative effectiveness for wear prevention of the different tested lubricants with and without antiwear additives. Even the thickness of the antiwear film and the amount of zinc (from zinc dialkyldithiophosphates used as antiwear additives) can be measured by this method.

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“…For example, sulfur-containing additives react to form a sulfide, and those containing chlorine form low-friction ferrous chloride layers on iron [1][2][3][4][5][6][7][8][9], and more complex additives such as zinc dialkyl dithiophosphate have correspondingly more complex surface chemistry, ultimately resulting in the formation of a glassy anti-wear film [10][11][12][13][14][15]. Such film-forming surface reactions can be thought of as occurring in two steps, the first being the adsorption of the additive onto the surface, followed by a chemical reaction to form the surface film.…”

Section: Introductionmentioning

confidence: 99%

“…Since the wear rate increases with increasing load, and higher normal loads lead to higher interfacial temperatures due to Joule (frictional) heating, lubricant additives should ideally react more rapidly with increasing temperature, and this is generally found to be the case [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15]17]. That is, the film growth kinetics of the additive respond to the severity of the tribological conditions.…”

Section: Introductionmentioning

confidence: 99%

Surface and Tribological Chemistry of Water and Carbon Dioxide on Copper Surfaces

Furlong

Gao

2008

Tribol Lett

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The tribological chemistry of carbon dioxide and water vapor is studied on copper surfaces at high pressures, with a view to understand the gas-phase lubrication of copper-copper sliding contacts. The adsorption and film formation properties are studied on vapor-deposited copper films in an ultrahigh vacuum chamber using a quartz crystal microbalance. The nature of the reactively formed film is studied after reaction by ex situ X-ray photoelectron spectroscopy (XPS). Carbon dioxide adsorbs reversibly on copper, while water vapor adsorbs both reversibly and irreversibly, where XPS reveals that the irreversibly formed film consists of a mixture of cuprous oxide/hydroxide. Measuring the thickness of the cuprous oxide/hydroxide film as a function of water vapor pressure and temperature reveals that its thickness varies between about 6 and 14 Å and is proportional to the total amount of water adsorbed on the surface. This results in a cuprous oxide/hydroxide film that is thinner at higher temperatures.

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Cited by 96 publications

References 26 publications

Chemical characterization and nanomechanical properties of antiwear films fabricated from ZDDP on a near hypereutectic Al–Si alloy

Chemical characterization and nanomechanical properties of antiwear films fabricated from ZDDP on a near hypereutectic Al–Si alloy

A Novel Method for Quantitative Determination of Ultra-low Wear Rates of Materials, Part I: On Steels

Surface and Tribological Chemistry of Water and Carbon Dioxide on Copper Surfaces

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