ast laser surface texturing of spherical samples to improve the frictional performance of elasto-hydrodynamic lubricated contact

Author(s)

Boidi, G. ^{[1, 2, 3]} ; Gruetzmacher, P. G. ^{[4, 5]} ; Kadiric, A. ^[2] ; Profito, F. J. ^[1] ; Machado, I. F. ^[1] ; Gachot, C. ^[5] ; Dini, D. ^[2]

Affiliation

^[1] Univ Sao Paulo, Polytech Sch, BR-05508030 Sao Paulo - Brazil

^[2] Imperial Coll London, Dept Mech Engn, South Kensington Campus, London SW7 2AZ - England

^[3] AC2T Res GmbH, A-2700 Wiener Neustadt - Austria

^[4] Saarland Univ, Dept Mat Sci & Engn, D-66123 Saarbrucken - Germany

^[5] TU Wien, Dept Engn Design & Prod Dev, A-1060 Vienna - Austria

• Document type: Journal article
• Source: FRICTION; v. 9, n. 5, p. 1227-1241, OCT 2021.
• Web of Science Citations: 9

Abstract

Textured surfaces offer the potential to promote friction and wear reduction by increasing the hydrodynamic pressure, fluid uptake, or acting as oil or debris reservoirs. However, texturing techniques often require additional manufacturing steps and costs, thus frequently being not economically feasible for real engineering applications. This experimental study aims at applying a fast laser texturing technique on curved surfaces for obtaining superior tribological performances. A femtosecond pulsed laser (Ti:Sapphire) and direct laser interference patterning (with a solid-state Nd:YAG laser) were used for manufacturing dimple and groove patterns on curved steel surfaces (ball samples). Tribological tests were carried out under elasto-hydrodynamic lubricated contact conditions varying slide-roll ratio using a ball-on-disk configuration. Furthermore, a specific interferometry technique for rough surfaces was used to measure the film thickness of smooth and textured surfaces. Smooth steel samples were used to obtain data for the reference surface. The results showed that dimples promoted friction reduction (up to 20%) compared to the reference smooth specimens, whereas grooves generally caused less beneficial or detrimental effects. In addition, dimples promoted the formation of full film lubrication conditions at lower speeds. This study demonstrates how fast texturing techniques could potentially be used for improving the tribological performance of bearings as well as other mechanical components utilised in several engineering applications. (AU)

• FAPESP's process: 17/21151-8 - Tribological effect of micro surface irregularities (surface porosity and texture) on lubricated sliding/rolling tests
• Grantee: Guido Boidi
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate (Direct)
• FAPESP's process: 16/25067-9 - Study of the micro surface irregularities (texture and porosity) effect on the tribological behavior of a steel sintered by SPS
• Grantee: Guido Boidi
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)