Friction of Undulated Surfaces Coated with MoS2 by Pulsed Laser Deposition

• Published in: Tribology transactions 1999-07, Vol.42 (3), p.495-502
• Main Authors: Mosleh, Mohsen, Laube, Samuel J. P., Suh, Nam P.
• Format: Article
• Language: English
• Subjects: Applied sciences; Contact of materials. Friction. Wear; Exact sciences and technology; Friction, wear, lubrication; Machine components; Mechanical engineering. Machine design; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Metals. Metallurgy; Molybdenum Disulfide; Plowing; Solid Lubricant; Wear Particles
• ISSN: 1040-2004; 1547-397X
• DOI: 10.1080/10402009908982246

Solid lubricants such as molybdenum disulfide can provide very low friction, but their effectiveness especially in the geometrically constrained sliding pairs is limited by plowing of coated surfaces by wear particles. Even in the presence of solid lubricants wear particles cause higher friction by plowing the interface. To minimize plowing, undulated surfaces with microgrooves perpendicular to the sliding direction can be used to trap wear particles. Smooth and undulated stainless steel surfaces were coated with molybdenum disulfide by pulsed laser deposition (PLD) and friction tested. Under identical test conditions, the friction coefficient of coated undulated surfaces is between 20-40 percent lower than that of coated smooth surfaces. The friction coefficient of undulated uncoated surfaces is about 100-350 percent less than that of smooth uncoated surfaces. Moreover, the entrapment of wear particles at the interfaces of geometrically constrained bearings may lead to seizure even when bearing surfaces are coated with solid lubricants. The use of undulated surf aces on these sliding systems has shown improved operating time and a reduced maintenance cycle. Presented at the 53rd Annual Meeting in Detroit, Michigan May 17-21, 1998