Nonequilibrium molecular dynamics simulations of stearic acid adsorbed on iron surfaces with nanoscale roughness

Ewen, James P.; Restrepo, Sebastián Echeverri; Morgan, Neal; Dini, Daniele

doi:10.1016/j.triboint.2016.11.039

Cited by 68 publications

(65 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Ewen et al [244] also used NEMD simulations to examine the structure and friction of OFM (stearic acid) films adsorbed on iron surfaces with random nanoscale roughness (0.2−0.8 nm root-mean-squared). The OFMs were strongly adsorbed, were not squeezed out, and prevented direct contact of asperities under the high pressures simulated (0.5−2.0 GPa).…”

Section: Friction Behaviourmentioning

confidence: 99%

Advances in nonequilibrium molecular dynamics simulations of lubricants and additives

2018

View full text Add to dashboard Cite

Nonequilibrium molecular dynamics (NEMD) simulations have provided unique insights into the nanoscale behaviour of lubricants under shear. This review discusses the early history of NEMD and its progression from a tool to corroborate theories of the liquid state, to an instrument that can directly evaluate important fluid properties, towards a potential design tool in tribology. The key methodological advances which have allowed this evolution are also highlighted. This is followed by a summary of bulk and confined NEMD simulations of liquid lubricants and lubricant additives, as they have progressed from simple atomic fluids to ever more complex, realistic molecules. The future outlook of NEMD in tribology, including the inclusion of chemical reactivity for additives, and coupling to continuum methods for large systems, is also briefly discussed.

show abstract

Section: Friction Behaviourmentioning

confidence: 99%

Advances in nonequilibrium molecular dynamics simulations of lubricants and additives

2018

View full text Add to dashboard Cite

show abstract

“…In this study, the order of the alkyl side chains to the amorphous carbon surface was simulated and the friction coefficient at different values of shear velocities was predicted . Ewen et al also reported the friction of IL lubricants at iron surfaces by non‐equilibrium molecular simulations . They investigated the effect of the load, shear velocity, surface topology, and ILs on the frictional forces and the simulation results are comparable to the experimental data …”

Section: Ionic Liquid Thin Films As Boundary Lubricantsmentioning

confidence: 59%

“…Ewen et al also reported the friction of IL lubricants at iron surfaces by non‐equilibrium molecular simulations . They investigated the effect of the load, shear velocity, surface topology, and ILs on the frictional forces and the simulation results are comparable to the experimental data …”

Section: Ionic Liquid Thin Films As Boundary Lubricantsmentioning

confidence: 87%

Nanometer‐Thick Ionic Liquids as Boundary Lubricants

Gong

2017

Adv Eng Mater

View full text Add to dashboard Cite

Ionic liquids (ILs) are fascinating materials with unique combination of solid and liquid properties. Due to high thermal stability and promising tribological properties, there have been increasing research interests in applying ILs as boundary lubricants. In this review, the authors will discuss the recent progress on this topic with the emphasis on the relationship between the molecular arrangement of ILs confined to a solid and the tribological properties. First, the fundamentals on boundary lubrication and the state-ofthe-art lubricants will be reviewed briefly. Second, the progress on the molecular structure of ILs confined to a solid surface will be discussed. Afterward, the experimental and computational efforts on the ILs as boundary lubricants will be discussed in details with emphasis on the effect of IL structure, solid substrates, and IL-soild interaction. Finally, the future research directions will be discussed.

show abstract

“…Here, the two fretting interfaces are separated by a constant distance of 12 Å to mimic the real working conditions. This is achieved by supplying the equivalent vibrational loads during minute fretting motion while simplifying the simulation by simulating the fretting stroke via the periodical frictional contact process [29]. The selected separation guarantees that there will be no force interaction for the upper and lower substrates.…”

Section: Fretting Layer Configurationmentioning

confidence: 99%

“…During the simulation, the friction and normal force values are important factors that need to be considered. After the simulation was started and when the original system reached equilibrium [29], the force responses were regarded as zero to rule out the Derjaguin effect. The friction and the normal force to friction were treated as relative values to describe the changes during the fretting processes as presented in Figs.…”

Section: General Trendmentioning

confidence: 99%

Multiscale analysis of friction behavior at fretting interfaces

et al. 2020

View full text Add to dashboard Cite

Friction behavior at fretting interfaces is of fundamental interest in tribology and is important in material applications. However, friction has contact intervals, which can accurately determine the friction characteristics of a material; however, this has not been thoroughly investigated. Moreover, the fretting process with regard to different interfacial configurations have also not been systematically evaluated. To bridge these research gaps, molecular dynamics (MD) simulations on Al-Al, diamond-diamond, and diamond-silicon fretting interfaces were performed while considering bidirectional forces. This paper also proposes new energy theories, bonding principles, nanoscale friction laws, and wear rate analyses. With these models, semi-quantitative analyses of coefficient of friction (CoF) were made and simulation outcomes were examined. The results show that the differences in the hardness, stiffness modulus, and the material configuration have a considerable influence on the fretting process. This can potentially lead to the force generated during friction contact intervals along with changes in the CoF. The effect of surface separation can be of great significance in predicting the fretting process, selecting the material, and for optimization.

show abstract

Nonequilibrium molecular dynamics simulations of stearic acid adsorbed on iron surfaces with nanoscale roughness

Cited by 68 publications

References 46 publications

Advances in nonequilibrium molecular dynamics simulations of lubricants and additives

Advances in nonequilibrium molecular dynamics simulations of lubricants and additives

Nanometer‐Thick Ionic Liquids as Boundary Lubricants

Multiscale analysis of friction behavior at fretting interfaces

Contact Info

Product

Resources

About