Tribology of pulsed laser deposited thin films of cesium oxythiomolybdate (Cs 2MoOS 3)

• Published in: Thin solid films 2002-03, Vol.406 (1), p.174-184
• Main Authors: Strong, Karla L, Zabinski, Jeffrey S
• Format: Article
• Language: English
• Subjects: Cesium oxythiomolybdate (Cs 2MoOS 3); Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Laser deposition; Materials science; Mechanical and acoustical properties; Methods of deposition of films and coatings; film growth and epitaxy; Physical properties of thin films, nonelectronic; Physics; Raman scattering; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Tribology; X-Ray photoelectron spectroscopy
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/S0040-6090(01)01744-8

High temperature solid lubricants are required for use on silicon nitride bearings with application temperatures of 600 °C and beyond. In the present research, the tribological properties of cesium oxythiomolybdate (Cs 2MoOS 3) thin films grown via pulsed laser deposition were studied as a function of temperature from 25 to 800 °C. When deposited on Si 3N 4, the coefficient of friction, μ, was 0.03 at 600 °C. When deposited on Al 2O 3, ZrO 2 and Inconel, μ≈0.15 at 600 °C. The friction coefficient generally increased with decreasing temperature. Wear rates were low on all substrates between 400 and 600 °C. Friction remained low up to 750 °C on Si 3N 4 substrates, but failure occurred above 750 °C. The tribomechanisms are discussed.