Film Forming Capability of Polymer-Base Oil Lubricants in Elastohydrodynamic and Very Thin Film Regimes

2019 ◽  
Vol 67 (2) ◽  
Author(s):  
Pauline Cusseau ◽  
Philippe Vergne ◽  
Laetitia Martinie ◽  
David Philippon ◽  
Nicolas Devaux ◽  
...  
Keyword(s):  
Thin Film ◽  
Base Oil ◽  
Film Forming

Clean Electron Microscope Substrate Films Used for Micrometeorite Collection and Study

1967 ◽  
Vol 25 ◽  
pp. 366-367
Author(s):  
D. M. Davies ◽  
R. Kemner ◽  
E. F. Fullam
Keyword(s):  
Thin Film ◽  
Electron Microscope ◽  
High Altitude ◽  
Amyl Acetate ◽  
Temperature Variations ◽  
Film Forming ◽  
Film Specimen ◽  
Particulate Contaminants

All serious electron microscopists at one time or another have been concerned with the cleanliness and freedom from artifacts of thin film specimen support substrates. This is particularly important where there are relatively few particles of a sample to be found for study, as in the case of micrometeorite collections. For the deposition of such celestial garbage through the use of balloons, rockets, and aircraft, the thin film substrates must have not only all the attributes necessary for use in the electron microscope, but also be able to withstand rather wide temperature variations at high altitude, vibration and shock inherent in the collection vehicle's operation and occasionally an unscheduled violent landing.Nitrocellulose has been selected as a film forming material that meets these requirements yet lends itself to a relatively simple clean-up procedure to remove particulate contaminants. A 1% nitrocellulose solution is prepared by dissolving “Parlodion” in redistilled amyl acetate from which all moisture has been removed.

Bridging high pressure rheology and film-forming capacity of polymer-base oil solutions in EHL

2016 ◽  
Vol 93 ◽  
pp. 502-510 ◽  
Author(s):  
C. Mary ◽  
D. Philippon ◽  
N. Devaux ◽  
N. Fillot ◽  
D. Laurent ◽  
...  
Keyword(s):  
High Pressure ◽  
Base Oil ◽  
Film Forming

The behaviour of lubricants in elastohydrodynamic contacts

1997 ◽  
Vol 211 (2) ◽  
pp. 91-106 ◽  
Author(s):  
A. J. Moore
Keyword(s):  
Thin Film ◽  
Physical Explanation ◽  
Ehd Lubrication ◽  
Film Forming ◽  
Theoretical Investigations ◽  
Research Findings ◽  
Rheological Modelling ◽  
Similarities And Differences ◽  
Forming Behaviour ◽  
Made In

Difficulties once found in accounting for the tractional behaviour of lubricants in elastohydrodynamic (EHD) contacts have largely been resolved. A wealth of research stimulated by this problem has gradually unravelled the underlying rheological complexities and laid the basis for a coherent physical explanation. The understanding achieved and the problems that remain are briefly reviewed. Despite the advances made in rheological modelling, developments are not readily taken up by those engaged in theoretical investigations. Although computational complexity must inevitably rise when lubricants are modelled realistically, the penalty for not doing so must be clearly understood. The implications can be readily devined from previous research findings. Progress made in the exploration of EHD film thickness is also examined. Similarities and differences in film-forming behaviour in thick film (> 0.1 μm) and thin film (< 0.1 μm) regimes are identified and consideration given to the interpretational difficulties that may arise as EHD and boundary regimes begin to merge. Finally, a few observations are made on the value of EHD lubrication studies to automotive engineering.

scholarly journals Film forming behavior in thin film lubrication at high speeds

Friction ◽  
2017 ◽  
Vol 6 (2) ◽  
pp. 156-163 ◽  
Author(s):  
He Liang ◽  
Dan Guo ◽  
Jianbin Luo
Keyword(s):  
Thin Film ◽  
Thin Film Lubrication ◽  
High Speeds ◽  
Film Forming ◽  
Film Lubrication

The impact of heat treatment technology and parameters on TiO2 thin film forming

2019 ◽  
Author(s):  
Jing Zhang ◽  
Shihua Ding ◽  
Mengxin Yuan ◽  
Xiaobo Tian ◽  
Wengang Yin ◽  
...  
Keyword(s):  
Thin Film ◽  
Heat Treatment ◽  
Tio2 Thin Film ◽  
Treatment Technology ◽  
Heat Treatment Technology ◽  
Film Forming ◽  
The Impact

Correlation Between Film Forming Ability and Rheological Properties of New and Aged Lowsaps Automotive Lubricants

2007 ◽  
Author(s):  
C. Meunier ◽  
D. Mazuyer ◽  
P. Vergne ◽  
M. El Fassi ◽  
J. Obiols
Keyword(s):  
Thin Film ◽  
Film Thickness ◽  
Rheological Parameters ◽  
Cross Model ◽  
Polymer Relaxation ◽  
Film Forming ◽  
Rheological Modelling ◽  
The One ◽  
Thinning Effect ◽  
Low Shear

The rheological behavior of fresh and aged diesel LowSaps 5W30 lubricant, is studied with both ElastoHydroDynamic tribometer, and low shear and high shear viscometers. The evolution of the film thickness in EHD contact, that varies between 1nm and 150 nm, displays two types of lubrication process according to rolling speed. On the one hand, a classical EHD behaviour, controlled by viscosity, may be observed beyond 35 nm with a significant shear thinning effect in the range of temperatures. On the other hand, below 35nm, a steep drop of film thickness indicates the unability of the viscosity improver polymer to form a thin film within the contact. These observations are closely related to rheological measurements carried out in a shear rate range from 10s−1 to 107s−1, and temperatures between 25°C and 150°C. Indeed, analysis of two rheological parameters, polymer relaxation time and hydrodynamic radius, may explain non newtonian and thin film effects in the EHD experiments. A rheological modelling based on the Cross model is developed to calculate these parameters. Then, the principle of time-temperature equivalence is used to map the characteristics of lubricants. Finally, the approach coupling EHD tribometer\Viscometer is applied to lubricants which have been degraded during a light duty diesel engine test.

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