High-temperature tribological characteristics of silver and gold coatings on ceramics prepared by ion-beam-assisted deposition

Conference · Wed Apr 01 00:00:00 EST 1992

OSTI ID:5072162

Erdemir, A; Erck, R A; Fenske, G R; Nichols, F A

An ion-beam-assisted deposition (IBAD) system was used to deposit silver and gold coatings on polycrystalline {alpha}-alumina (Al{sub 2}O{sub 3}) substrates for tribological studies at temperatures to 400{degrees}C. The wear tests were performed with an oscillating ball-on-flat type of test apparatus as a partial simulation of ring/liner motion and contact geometry in actual engine systems. The test results showed that without a surface coating, both the wear rates and the friction coefficients of Al{sub 2}O{sub 3}/Al{sub 2}O{sub 3} test pairs were quite high, and increased substantially with temperature. In contract, the wear of flats coated with silver and gold was at unmeasurable levels, even after sliding tests of 110,000 passes. The wear of balls (uncoated) sliding against the Ag- and Au-coated flats was reduced by factors of 45 to more than 500 depending on coating type and ambient temperature. The friction coefficients of pairs with an IBAD-Ag or Au coating were in the range of 0.32--0.5.

• Research Organization: Argonne National Lab., IL (United States)
• Sponsoring Organization: USDOE; USDOE, Washington, DC (United States)
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 5072162
• Report Number(s): ANL/CP-76056; CONF-9208102-1; ON: DE92016776
• Resource Relation: Conference: China international symposium for youth tribologists, Lanzhou (China), 10-14 Aug 1992
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COATINGS
TRIBOLOGY
GOLD
DEPOSITION
SILVER
ALUMINIUM OXIDES
FRICTION
ION BEAMS
SCANNING ELECTRON MICROSCOPY
WEAR
ALUMINIUM COMPOUNDS
BEAMS
CHALCOGENIDES
ELECTRON MICROSCOPY
ELEMENTS
METALS
MICROSCOPY
OXIDES
OXYGEN COMPOUNDS
TRANSITION ELEMENTS
360103* - Metals & Alloys- Mechanical Properties
360101 - Metals & Alloys- Preparation & Fabrication