Controlling Friction With External Electric or Magnetic Fields: 25 Examples

Krim, J.

doi:10.3389/fmech.2019.00022

Cited by 38 publications

(39 citation statements)

References 60 publications

(104 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It has also been suggested that applied electrical potentials may be used to prevent corrosive damage to cutting tools [135], reduce torque at the drilling mud-drill string interface [136], help release stuck drill-pipes [137], reduce energy consumption in wire drawing [120,121], improve chemical mechanical planarisation of microelectronic wafers [9] and even reduce plough/soil friction [138]. There are, no doubt others, but the extent to which any of these have been implemented in practice is not clear.…”

Section: Aqueous Lubricantsmentioning

confidence: 99%

“…In 2012, Lvovich examined the application of electrochemical impedance spectroscopy to study industrial lubricants [6], while in 2015 Xie et al considered the very wide range of phenomena possible when charged surfaces were generated in lubricated contacts [7]. Very recently, Jiang et al have considered the impact of electric and magnetic fields on the main lubrication regimes from a primarily mechanistic point of view [8], while Krim has used a series of case study examples to describe how applied electrical and magnetic fields can be used to control friction actively [9].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Triboelectrochemistry: Influence of Applied Electrical Potentials on Friction and Wear of Lubricated Contacts

Spikes

2020

Tribol Lett

View full text Add to dashboard Cite

Research on the effects of applied electrical potential on friction and wear, a topic sometimes termed “Triboelectrochemistry”, has been reviewed. Historically, most such research has focussed on aqueous lubricants, whose relatively high electrical conductivities enable use of three-electrode electrochemical kinetic techniques, in which the electrode potential at a single electrode | fluid interface is controlled relative to a suitable reference electrode. This has led to identification of several different mechanisms by which applied electrode potentials can influence friction and wear. Of these, the most practically important are: (i) promotion of adsorption/desorption of polar additives on tribological surfaces by controlling the latters’ surface charges; (ii) stimulation or suppression of redox reactions involving either oxygen or lubricant additives at tribological surfaces. In recent years, there has been growing interest in the effects of applied electrical potentials on rubbing contacts lubricated by non-aqueous lubricants, such as ester- and hydrocarbon-based oils. Two different approaches have been used to study this. In one, a DC potential difference in the mV to V range is applied directly across a thin film, lubricated contact to form a pair of electrode | fluid interfaces. This has been found to promote some additive reactions and to influence friction and wear. However, little systematic exploration has been reported of the underlying processes and generally the electrode potentials at the interfaces have not been well defined. The second approach is to increase the conductivity of non-aqueous lubricants by adding secondary electrolytes and/or using micro/nanoscale electrodes, to enable the use of three-electrode electrochemical methods at single metal | fluid interfaces, with reference and counter electrodes. A recent development has been the introduction of ionic liquids as both base fluids and lubricant additives. These have relatively high electrical conductivities, allowing control of applied electrode potentials of individual metal | fluid interfaces, again with reference and counter electrodes. The broadening use of “green”, aqueous-based lubricants also enlarges the possible future scope of applied electrode potentials in tribology. From research to date, there would appear to be considerable opportunities for using applied electrical potentials both to promote desirable and to supress unwanted lubricant interactions with rubbing surfaces, thereby improving the tribological performance of lubricated machine components. Graphical Abstract

show abstract

Section: Aqueous Lubricantsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Triboelectrochemistry: Influence of Applied Electrical Potentials on Friction and Wear of Lubricated Contacts

Spikes

2020

Tribol Lett

View full text Add to dashboard Cite

show abstract

“…[7,38] Such highly specific scenarios have not yet been verified, although they would offer promising methods to control friction by tailoring electric fields. [45] In this paper, we investigate nanoscale single asperity sliding friction at the surface of La (1−x) Sr x MnO 3 (LSMO) films (x = 0.2 and 0.3) while heating through transitions from the ferromagnetic (FM) metal to a paramagnetic polaronic conductor (PM) state. The transitions in these films allow us to probe the effect of electronic and phononic degrees of freedom on friction without a change in the crystal structure.…”

Section: Introductionmentioning

confidence: 99%

Polaronic Contributions to Friction in a Manganite Thin Film

et al. 2021

View full text Add to dashboard Cite

Despite the huge importance of friction in regulating movement in all natural and technological processes, the mechanisms underlying dissipation at a sliding contact are still a matter of debate. Attempts to explain the dependence of measured frictional losses at nanoscale contacts on the electronic degrees of freedom of the surrounding materials have so far been controversial. Here, it is proposed that friction can be explained by considering the damping of stick-slip pulses in a sliding contact. Based on friction force microscopy studies of La (1−x) Sr x MnO 3 films at the ferromagnetic-metallic to a paramagnetic-polaronic conductor phase transition, it is confirmed that the sliding contact generates thermally-activated slip pulses in the nanoscale contact, and argued that these are damped by direct coupling into the phonon bath. Electron-phonon coupling leads to the formation of Jahn-Teller polarons and to a clear increase in friction in the high-temperature phase. There is neither evidence for direct electronic drag on the atomic force microscope tip nor any indication of contributions from electrostatic forces. This intuitive scenario, that friction is governed by the damping of surface vibrational excitations, provides a basis for reconciling controversies in literature studies as well as suggesting possible tactics for controlling friction.

show abstract

“…Recently, many researchers have argued the use of external energy sources, e. g., electrical and magnetic fields, pulsed and direct electrical currents, represents an intensively developing research domain in the field of plastic deformation in metallic materials [1][2][3][4][5].…”

Section: Introductionmentioning

confidence: 99%

The influence of electrical potential on the mechanical properties of commercially pure titanium

et al. 2020

View full text Add to dashboard Cite

The mechanical behavior of metallic materials exposed to external energy sources e. g. electric potentials, direct and pulsed currents as well as magnetic fields is a key aspect in assessing the material usability in present day industries. Recent researches have shown that the mechanical properties of materials are sensitive to the state of thin near-surface layers. This state can be changed by an electrical potential that can influence on the energy density of the surface. The paper discusses the effect of electrical potentials (values from 0 to 1 V) on the mechanical properties (microhardness and elastic modulus) of the commercially pure titanium grade 2. It was revealed that the microhardness increased by 11 % at 1 V compared to the initial state. As regards elastic modulus, its values gradually increased from around 100 GPa at 0 V to 300 GPa at 1 V. It has been suggested that the increase of the microhardness and elastic modulus relates to the changes in surface tension of titanium samples. An analysis of the surface tension's dependence upon an electrical potential was carried out in terms of an electric double layer concept. It was shown that the surface tension coefficient has quadratic dependent on electric potential.

show abstract

Controlling Friction With External Electric or Magnetic Fields: 25 Examples

Cited by 38 publications

References 60 publications

Triboelectrochemistry: Influence of Applied Electrical Potentials on Friction and Wear of Lubricated Contacts

Triboelectrochemistry: Influence of Applied Electrical Potentials on Friction and Wear of Lubricated Contacts

Polaronic Contributions to Friction in a Manganite Thin Film

The influence of electrical potential on the mechanical properties of commercially pure titanium

Contact Info

Product

Resources

About