Analysis of CNT additives in porous layered thin film lubrication with electric double layer

Author(s):  
T. V. V. L. N. Rao ◽  
A. M. A. Rani ◽  
S. Sufian ◽  
N. M. Mohamed
Author(s):  
X. J. Wang ◽  
S. X. Bai ◽  
P. Huang

Theoretical and experimental researches have showed that electro-viscosity induced by electric double layer influences apparently on thin film lubrication. In order to consider the influence of electric double layer, in the present paper, experiments are carried out on a self-made oil lubrication tester with a composite sliding block and with adding an external electric field to reconstruct electric double layer. The results show that electric double layer has an apparent effect on friction coefficient. To ensure the results, further experiments are carried out with additives’ being added to change the ionic concentration of lubricants. The results indicate that electric double layer has more apparent effect on friction coefficient in thin film lubrication.


2014 ◽  
Vol 925 ◽  
pp. 538-542 ◽  
Author(s):  
T.V.V.L.N. Rao ◽  
S. Sufian ◽  
Norani Muti Mohamed

This paper presents a model of electro-viscosity considering effects of electric double layer on thin film lubrication with partial slip. The apparent viscosity and modified Reynolds equation are derived with consideration of electric double layer with partial slip. The apparent viscosity includes the combined effects of the electro-viscosity, the viscosity of bulk fluid and slip length. The electro-viscosity depends on the zeta potential. The effects of electric double layer with partial boundary slip on load capacity are analyzed for one-dimensional slider bearing. The electric double layer leads to an increase in apparent viscosity of lubricant and hence load capacity in thin film lubrication. Electric double layer with partial slip on parallel bearing surfaces increases the bearing load capacity.


Friction ◽  
2021 ◽  
Author(s):  
Thi D. Ta ◽  
Hien D. Ta ◽  
Kiet A. Tieu ◽  
Bach H. Tran

AbstractThe rapid development of molecular dynamics (MD) simulations, as well as classical and reactive atomic potentials, has enabled tribologists to gain new insights into lubrication performance at the fundamental level. However, the impact of adopted potentials on the rheological properties and tribological performance of hydrocarbons has not been researched adequately. This extensive study analyzed the effects of surface structure, applied load, and force field (FF) on the thin film lubrication of hexadecane. The lubricant film became more solid-like as the applied load increased. In particular, with increasing applied load, there was an increase in the velocity slip, shear viscosity, and friction. The degree of ordering structure also changed with the applied load but rather insignificantly. It was also significantly dependent on the surface structure. The chosen FFs significantly influenced the lubrication performance, rheological properties, and molecular structure. The adaptive intermolecular reactive empirical bond order (AIREBO) potential resulted in more significant liquid-like behaviors, and the smallest velocity slip, degree of ordering structure, and shear stress were compared using the optimized potential for liquid simulations of united atoms (OPLS-UAs), condensed-phase optimized molecular potential for atomic simulation studies (COMPASS), and ReaxFF. Generally, classical potentials, such as OPLS-UA and COMPASS, exhibit more solid-like behavior than reactive potentials do. Furthermore, owing to the solid-like behavior, the lubricant temperatures obtained from OPLS-UA and COMPASS were much lower than those obtained from AIREBO and ReaxFF. The increase in shear stress, as well as the decrease in velocity slip with an increase in the surface potential parameter ζ, remained conserved for all chosen FFs, thus indicating that the proposed surface potential parameter ζ for the COMPASS FF can be verified for a wide range of atomic models.


RSC Advances ◽  
2021 ◽  
Vol 11 (29) ◽  
pp. 17910-17913
Author(s):  
Liuhui Lei ◽  
Yuanyuan Tan ◽  
Xing Yuan ◽  
Wei Dou ◽  
Jiale Zhang ◽  
...  

Flexible electric-double-layer (EDL) thin film transistors (TFTs) based on a vertical InGaZnO4 (IGZO) channel are fabricated at room temperature.


1965 ◽  
Vol 87 (3) ◽  
pp. 735-739 ◽  
Author(s):  
Y. Tamai ◽  
B. G. Rightmire

Experimental work was carried out on the boundary lubrication of a copper-copper couple with pure cetane, palmitic acid solution of cetane, and some other organic materials. The purpose was to get information about α and μlube, which appear in the friction equation: μ=αμsolid+(1−α)μlube, by using two different kinds of copper surface, a clean surface, and an oxidized surface. α was found to be small with palmitic acid solution, and the estimated shear strength of palmitic acid was high under the examined condition. α and μlube seemed to be properties which are independent of each other. α is closely related to the attraction force between the lubricant and the substrate, whereas μlube is related to the complexity of molecular structure of the lubricant. A comparison was made of bulk-liquid and thin-film lubrication. μlube was smaller in thin-film lubrication than it was in bulk-liquid lubrication. This suggests that the frictional resistance may be partly contributed by liquid in the edge space around the real contact.


Sign in / Sign up

Export Citation Format

Share Document