A low-to-high friction transition in gradient nano-grained Cu and Cu-Ag alloys

Chen, Xiang; Han, Z.

doi:10.1007/s40544-020-0440-x

Cited by 22 publications

(8 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…On the other hand, many reports show that friction can be reduced by treating a metal to induce a nanocrystalline surface layer [26][27][28][29][30] with the explanation being that a surface layer with nanosized grains has higher hardness because of the Hall-Petch effect, and this higher hardness reduces wear and friction. More recent work shows that gradients in grain size at a metal surface lead to a similar effect [31][32][33][34].…”

Section: Introductionmentioning

confidence: 97%

Atomic Origins of Friction Reduction in Metal Alloys

Cheng

Chandross

2021

Tribol Lett

View full text Add to dashboard Cite

We present the results of large scale molecular dynamics simulations aimed at understanding the origins of high friction coefficients in pure metals, and their concomitant reduction in alloys and composites. We utilize a series of targeted simulations to demonstrate that different slip mechanisms are active in the two systems, leading to differing frictional behavior. Specifically, we show that in pure metals, sliding occurs along the crystallographic slip planes, whereas in alloys shear is accommodated by grain boundaries. In pure metals, there is significant grain growth induced by the applied shear stress and the slip planes are commensurate contacts with high friction. However, the presence of dissimilar atoms in alloys suppresses grain growth and stabilizes grain boundaries, leading to low friction via grain boundary sliding.

show abstract

Section: Introductionmentioning

confidence: 97%

Atomic Origins of Friction Reduction in Metal Alloys

Cheng

Chandross

2021

Tribol Lett

View full text Add to dashboard Cite

show abstract

“…1) and it was about 0.89, similar to pure copper. In the work [ 44 ], the authors obtained a friction coefficient of 0.7–0.75 for pure copper in a friction pair with WC-Co, while for the Cu-5% Ag alloy it was in the range of 0.6–0.8. Such high coefficients of friction of pure metals or metal alloys are caused by plastic deformation, caused by sliding and subsequent changes in the microstructure beneath the worn surface [ 45 , 46 ].…”

Section: Resultsmentioning

confidence: 99%

Tribological Properties of Cu-MoS2-WS2-Ag-CNT Sintered Composite Materials

et al. 2022

View full text Add to dashboard Cite

In this work, in order to produce Cu-MoS2-WS2-Ag-CNT self-lubricating materials, powder metallurgy was used. Several different compositions containing single solid lubricant MoS2, WS2, Ag and CNTs as well as multi-component lubricants in the copper matrix were prepared. Friction and wear tests were carried out using the pin-on-disc method at room temperature. Light microscopy (LM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) were used to characterize the wear mechanism of sintered materials. The tribofilm on the worn surfaces of sintered materials and counter-specimens was observed. The influence of single solid lubricants and the synergistic interaction of two, three or four solid lubricants on tribological properties of sintered composite materials were determined.

show abstract

“…Metallic materials are widely used in industry and contribute significantly to national economic development. Unfortunately, most metals are characterized by high coefficients of friction (COFs) and poor anti-wear properties [1][2][3][4][5], which are detrimental to the safety, reliability, and efficiency of engineering components. To protect machinery and their parts from extreme wear, tremendous efforts are expended in depositing ceramic coatings on the surface of the metals via physical and chemical approaches, including thermal spraying [6,7], plasma electrolytic oxidation [8,9], and physical vapor deposition [10,11].…”

Section: Introduction mentioning

confidence: 99%

In-situ preparation of robust self-lubricating composite coating from thermally sprayed ceramic template

Wu¹,

Li²,

Fan³

et al. 2023

Journal of Advanced Ceramics

View full text Add to dashboard Cite

The self-lubricating ceramic coatings that can control friction and wear have attracted researchers' widespread attention. However, the poor interfacial bonding between lubricants and ceramics and the deterioration of mechanical properties due to a tribological design limit their practical applications. Here, a robust self-lubricating coating was fabricated by an in-situ synthesis of MoS 2 /C within inherent defects of thermally sprayed yttria-stabilized zirconia (YSZ) coatings. The edge-pinning by noncoherent endows hybrid coatings with excellent interfacial strength, increasing their hardness (HV) and cohesive strength. Furthermore, owing to the formation of a well-covered robust lubricating film at a frictional interface, a coefficient of friction (COF) can be reduced by 79.6% to 0.15, and a specific wear rate (W) drops from 1.36×10 −3 to 6.27×10 −7 mm 3 •N −1 •m −1 . Combining outstanding mechanical properties and tribological performance, the hybrid coating exhibits great application potential in controlling friction and wear. Importantly, this strategy of introducing the target materials into the inherent defects of the raw materials to improve the relevant properties opens new avenues for the design and preparation of composite materials.

show abstract

A low-to-high friction transition in gradient nano-grained Cu and Cu-Ag alloys

Cited by 22 publications

References 34 publications

Atomic Origins of Friction Reduction in Metal Alloys

Atomic Origins of Friction Reduction in Metal Alloys

Tribological Properties of Cu-MoS2-WS2-Ag-CNT Sintered Composite Materials

In-situ preparation of robust self-lubricating composite coating from thermally sprayed ceramic template

Contact Info

Product

Resources

About