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Grigory Ryk

Bio: Grigory Ryk is an academic researcher from Technion – Israel Institute of Technology. The author has contributed to research in topics: Piston & Cylinder (engine). The author has an hindex of 3, co-authored 4 publications receiving 563 citations.

Papers
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Journal ArticleDOI
TL;DR: In this paper, an experimental study is presented to evaluate the effectiveness of micro-surface structure, produced by laser texturing, to improve tribological properties of reciprocating automotive components, including piston rings and cylinder linings.
Abstract: An experimental study is presented to evaluate the effectiveness of micro-surface structure, produced by laser texturing, to improve tribological properties of reciprocating automotive components. The test rig and test specimens are described and some test results are presented. Good correlation is found with theoretical prediction of friction reduction on a simple, yet representative, test specimen. Potential benefit of the laser surface texturing under conditions of lubricant starvation is also presented. Finally, friction reduction with actual production piston rings and cylinder liner segments is demonstrated. Presented at the 57th Annual Meeting in Houston, Texas May 19–23, 2002

465 citations

Journal ArticleDOI
TL;DR: In this paper, the effect of partial laser surface texturing (LST) on friction reduction in piston rings was evaluated with flat and parallel test specimens with partial LST, confirming a previously published theoretical model and the advantage of partial over full LST.
Abstract: An experimental study is presented to evaluate the effect of partial laser surface texturing (LST) on friction reduction in piston rings. In a previous study, 30% friction reduction was obtained with full LST where the full width of the piston ring is textured with a very large number of microdimples that act individually as microhydrodynamic bearings. In partial LST, only a portion of the piston-ring width is textured with high dimple density, producing a “collective” effect of the dimples that provides an equivalent converging clearance even with nominally parallel mating surfaces. Experimental results obtained with flat and parallel test specimens with partial LST are presented, confirming a previously published theoretical model and the advantage of partial over full LST. Friction reduction by LST with actual production-crowned piston rings and cylinder liner segments is not straightforward and needs further investigation. Presented at the STLE Annual Meeting in Las Vegas, Nevada May 15-19, 2005 Revie...

137 citations

Journal ArticleDOI
TL;DR: In this article, the deformation-induced generation of a surface film consisting of low-shear-strength oil-retaining compounds is obtained via supplying chemically beneficial elements during a widely used surface finishing mechanical treatment.
Abstract: Advances toward low friction surfaces are in growing demand from many economic sectors for energy efficiency and environmental safety. However, the traditional approach of multi-grade oil formulation is limited by its inability to induce pollution-free generation of uniform oil-retaining films needed to improve surface lubricity. Here, a direct route to the formation of a surface layer of superior lubricity is presented as an alternative to the use of oil additives for friction reduction. The deformation-induced generation of a surface film consisting of low-shear-strength oil-retaining compounds is obtained via supplying chemically beneficial elements during a widely used surface finishing mechanical treatment. An ultra-low friction coefficient of about 0.01 is obtained with base oil lubrication after tailoring the surface chemistry by shot peening using a mixture of Cu2S and Al2O3; this result opens new horizons for surface engineering.

12 citations

Patent
01 Oct 2014
TL;DR: In this article, a low-friction film is formed by applying a mechanical finishing surface treatment to the surface and subjecting the surface to a friction reducing material which diffuses through the surface forming the self-regenerating low friction film.
Abstract: Aspects of the invention are related to an article comprising a low friction film and a method of forming the low friction film on a surface of the article. The low friction film may be formed by applying a mechanical finishing surface treatment to the surface and subjecting the surface to a friction reducing material which diffuses through the surface forming the self-regenerating low friction film. The low friction film comprises at least 1 atomic % of friction reducing material atoms based on the total atoms within the low friction film, such that the low friction film has a residual compressive stress larger than 10 MPa.

Cited by
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Journal ArticleDOI
TL;DR: In this paper, the authors present the state of the art in LST and the potential of this technology in various lubricated applications like mechanical seals, piston rings and thrust bearings.
Abstract: Surface texturing has emerged in the last decade as a viable option of surface engineering resulting in significant improvement in load capacity, wear resistance, friction coefficient etc. of tribological mechanical components. Various techniques can be employed for surface texturing but Laser Surface Texturing (LST) is probably the most advanced so far. LST produces a very large number of micro-dimples on the surface and each of these micro-dimples can serve either as a micro-hydrodynamic bearing in cases of full or mixed lubrication, a micro-reservoir for lubricant in cases of starved lubrication conditions, or a micro-trap for wear debris in either lubricated or dry sliding. The present paper reviews the current effort being made world wide on surface texturing in general and on laser surface texturing in particular. It presents the state of the art in LST and the potential of this technology in various lubricated applications like mechanical seals, piston rings and thrust bearings. The paper also describes some fundamental on going research around the world with LST.

1,123 citations

Journal ArticleDOI
01 Sep 2017-Friction
TL;DR: In this paper, the impact of friction and wear on energy consumption, economic expenditure, and CO2 emissions is presented on a global scale, covering four main energy consuming sectors: transportation, manufacturing, power generation, and residential.
Abstract: Calculations of the impact of friction and wear on energy consumption, economic expenditure, and CO2 emissions are presented on a global scale. This impact study covers the four main energy consuming sectors: transportation, manufacturing, power generation, and residential. Previously published four case studies on passenger cars, trucks and buses, paper machines and the mining industry were included in our detailed calculations as reference data in our current analyses. The following can be concluded: Fifty years ago, wear and wear-related failures were a major concern for UK industry and their mitigation was considered to be the major contributor to potential economic savings by as much as 95% in ten years by the development and deployment of new tribological solutions. The corresponding estimated savings are today still of the same orders but the calculated contribution to cost reduction is about 74% by friction reduction and to 26% from better wear protection. Overall, wear appears to be more critical than friction as it may result in catastrophic failures and operational breakdowns that can adversely impact productivity and hence cost.

966 citations

Proceedings ArticleDOI
01 Jan 2004-Volume!
TL;DR: Laser Surface Texturing (LST) is probably the most advanced surface texturing technique as mentioned in this paper and it produces a very large number of micro-dimples on the surface and each of these microdimples can serve either as a micro-hydrodynamic bearing in cases of full or mixed lubrication.
Abstract: Surface texturing has emerged in the last decade as a viable option of surface engineering resulting in significant improvement in load capacity, wear resistance, friction coefficient etc. of tribological mechanical components. Various techniques can be employed for surface texturing but Laser Surface Texturing (LST) is probably the most advanced so far. LST produces a very large number of micro-dimples on the surface and each of these micro- dimples can serve either as a micro-hydrodynamic bearing in cases of full or mixed lubrication, a micro-reservoir for lubricant in cases of starved lubrication conditions, or a micro-trap for wear debris in either lubricated or dry sliding. The paper reviews the current effort being made world wide on laser surface texturing in particular. It presents the state of the art in LST and the potential of this technology in various lubricated applications like mechanical seals, piston rings, thrust bearings, magnetic recording etc. The paper also describes some fundamental on-going research around the world with LST.

914 citations

Journal ArticleDOI
TL;DR: In this article, the authors report the advances in the state of the art considering the relationships between the properties of functional surfaces, their applications and the technologies to engineer surfaces, and their applications in many advanced fields, such as: electronics, information technology, energy, optics, tribology, biology and biomimetics.

593 citations

Journal ArticleDOI
TL;DR: In this paper, the authors provide a comparative summary of different modeling techniques for fluid flow, cavitation and micro-hydrodynamic effects for surface texturing, and provide the key findings.

590 citations