scholarly journals XANES Study of Tribofilm Formation With Low Phosphorus Additive Mixtures of Phosphonium Ionic Liquid and Borate Ester

2021 ◽  
Vol 7 ◽  
Author(s):  
Kimaya Vyavhare ◽  
Vibhu Sharma ◽  
Vinay Sharma ◽  
Ali Erdemir ◽  
Pranesh B. Aswath
Keyword(s):  
Ionic Liquid ◽  
Boron Oxide ◽  
Electrical Contact ◽  
Wear Volume ◽  
Electrical Contact Resistance ◽  
Test Configuration ◽  
Iron Phosphates ◽  
Borate Ester ◽  
Low Phosphorus ◽  
Boron Phosphates

The development of low phosphorus engine oils is important to minimize phosphorus-induced exhaust catalyst poisoning and resulting in harmful emissions. In this study, low phosphorus oil formulations were prepared by using an ashless additive mixture of borate ester (SB) with ionic liquid composed of a phosphonium cation and phosphate anion (P_DEHP) at 350 and 700 ppm phosphorus. Tribological properties of this binary additive system were evaluated using a reciprocating cylinder on a flat test configuration. Favorable interaction between P_DEHP and SB resulted in a significant reduction in friction coefficient and wear volume, in particular for P_DEHP(700P) + SB oil blend. Time-scale analysis of tribofilm formation was determined by running the tribological experiments for 5, 15, and 60 min duration. Electrical contact resistance (ECR) results revealed that the addition of P_DEHP at 350 ppm of phosphorus to SB at 500 ppm of boron can reduce the incubation time from 300 to 100 s for stable tribofilm formation. X-ray absorption near-edge spectroscopy (XANES) analysis of tribofilms indicates that the tribofilm mechanism for additive mixtures of P_DEHP and SB initially involves the formation of boron oxide-based films, which later interact with phosphorus to form boron phosphates in addition to iron phosphates. Incorporation of the high amount of boron phosphates in addition to boron oxide/acid and iron phosphates in the tribofilms contributed to the improved tribological performance of P_DEHP(700P) + SB oil. XANES results reveal that tribofilms formed due to the interaction of SB and P_DEHP evolve to a cross-linked structure, wherein the chain length of polyphosphates is increased with the increase in rubbing time.

scholarly journals The Route for Ultra-High Recording Density Using Probe-Based Data Storage Device

NANO ◽  
2015 ◽  
Vol 10 (08) ◽  
pp. 1550118 ◽  
Author(s):  
Lei Wang ◽  
Jing Wen ◽  
CiHui Yang ◽  
Shan Gai ◽  
YuanXiu Peng
Keyword(s):  
Phase Change ◽  
Data Storage ◽  
Electrical Contact ◽  
Crystal Nucleation ◽  
Access Time ◽  
Storage Device ◽  
Electrical Contact Resistance ◽  
Low Energy Consumption ◽  
Modeling Techniques ◽  
Second Period

Phase-change probe memory using Ge2Sb2Te5 has been considered as one of the promising candidates as next-generation data storage device due to its ultra-high density, low energy consumption, short access time and long retention time. In order to utmostly mimic the practical setup, and thus fully explore the potential of phase-change probe memory for 10 Tbit/in2 target, some advanced modeling techniques that include threshold-switching, electrical contact resistance, thermal boundary resistance and crystal nucleation-growth, are introduced into the already-established electrothermal model to simulate the write and read performance of phase-change probe memory using an optimal media stack design. The resulting predictions clearly demonstrate the capability of phase-change probe memory to record 10 Tbit/in2 density under pico Joule energy within micro second period.

Discrete drops in the electrical contact resistance during nanoindentation of a bulk metallic glass

2016 ◽  
Vol 108 (18) ◽  
pp. 181903 ◽  
Author(s):  
Gaurav Singh ◽  
R. L. Narayan ◽  
A. M. Asiri ◽  
U. Ramamurty
Keyword(s):  
Metallic Glass ◽  
Contact Resistance ◽  
Bulk Metallic Glass ◽  
Electrical Contact ◽  
Electrical Contact Resistance

Electroless Ag films for ionic liquid lubricated electrical contact

2021 ◽  
pp. 138818
Author(s):  
Feiyan Yuwen ◽  
Yanan Qiao ◽  
Zhiqin Ding ◽  
Bo Wang ◽  
Wu Zhang ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Electrical Contact

scholarly journals Study of the Lubricating Ability of Protic Ionic Liquid on an Aluminum–Steel Contact

Lubricants ◽  
2018 ◽  
Vol 6 (3) ◽  
pp. 66 ◽  
Author(s):  
Akshar Patel ◽  
Hong Guo ◽  
Patricia Iglesias
Keyword(s):  
Ionic Liquid ◽  
Friction And Wear ◽  
Constant Load ◽  
Economic Losses ◽  
Contact Friction ◽  
Wear Volume ◽  
Sliding Velocity ◽  
Protic Ionic Liquid ◽  
Wear Reduction ◽  
Pin On Disk

Contact friction between moving components leads to severe wear and failure of engineering parts, resulting in large economic losses. The lubricating ability of the protic ionic liquid, tri-[bis(2-hydroxyethylammonium)] citrate (DCi), was studied as a neat lubricant and as an additive in a mineral oil (MO) at various sliding velocities and constant load on an aluminum–steel contact using a pin-on-disk tribometer. Tribological tests were also performed at different concentrations of DCi. When DCi was used as an additive in MO, friction coefficient and wear volume were reduced for each sliding velocity, with a maximum friction and wear reduction of 16% and 40%, respectively, when 2 wt % DCi was added to MO at a sliding velocity of 0.15 m/s. Scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) were also applied to analyze the wear mechanism of the interface lubricated by MO and DCi as additive.

scholarly journals The Wear Process During the “Running-In” of Steel in Lubricated Sliding

1987 ◽  
Vol 109 (4) ◽  
pp. 587-591 ◽  
Author(s):  
M. Suzuki ◽  
K. C. Ludema
Keyword(s):  
Contact Resistance ◽  
Surface Film ◽  
Electrical Contact ◽  
Mineral Oil ◽  
Entrance Region ◽  
Engine Oil ◽  
Small Range ◽  
Electrical Contact Resistance ◽  
Metallic Contact ◽  
Wear Process

Steel cylinders were slid against flat steel disks, using a liquid lubricant, in order to study the progression of events associated with “running-in.” It was found that, when using mineral oil, the electrical contact resistance varied over a small range of high values indicating no metallic contact, whereas with engine oil a high resistance with an intermittent negligible contact resistance was found. A surface film forms from the additives in the engine oil which produces lower wear, slightly higher friction, a retarded running-in, and a rougher surface finish in the direction of sliding than does the mineral oil. A film which is composed only of Fe3O4 is formed when mineral oil is used. In addition, the mineral oil lubricated surfaces develop a conforming waviness across the sliding tracks. The oxide must have enhanced this surface conformity since it was not seen in the surfaces lubricated with engine oil. The role of the oxide may be further seen in experiments in which wear debris that accumulated in the entrance region of specimen contact was removed at frequent intervals. Little conforming waviness was seen in the latter case, suggesting that oxide which gathered in the entrance region abraded grooves in the steel surfaces. After the oxides were dislodged the friction increased and the contact resistance decreased for a time, indicating that the oxide acted like a solid lubricant.

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