The Evaluation of a Modified Chrome Oxide Based High Temperature Solid Lubricant Coating for Foil Gas Bearings
This paper describes the friction and wear performance of PS304, a modified chrome oxide based coating, for foil gas bearings. PS304 contains 60 wt. % NiCr binder, 20 wt. % Cr203 hardener, and 10 wt. % each Ag and BaF2ICaF2 lubricants. For evaluation, the coating is plasma spray deposited onto test journals which are slid against a superalloy partial arc foil bearing. The test load was 10 KPa (1.5 psi) and the bearings were run under start/stop cyclic conditions. The data show good wear performance of the bearing especially at temperatures above 25 °C. Bearing friction was moderate (μ ≤≈0.4) over the entire temperature range. Based upon the results obtained, the PS304 coating has promise for high temperature, oil-free turbomachinery applications. Presented at the 54th Annual Meeting Las Vegas, Nevada May 23–27, 1999
Preliminary evaluation of PS300: A new self-lubricating high temperature composite coating for use to 800{degrees}C
This paper introduces PS300, a plasma sprayed, self-lubricating composite coating for use in sliding contacts at temperatures to 800{degrees}C. PS300 is a metal bonded chrome oxide coating with silver and BaF{sub 2}/CaF{sub 2} eutectic solid lubricant additives. PS300 is similar to PS200, a chromium carbide based coating; which is currently being investigated for a variety of tribological applications. In pin-on-disk testing up to 650{degrees}C, PS300 exhibited comparable friction and wear properties to PS200. The PS300 matrix, which is predominantly chromium oxide rather than chromium carbide, does not require diamond grinding and polishes readily with silicon carbide abrasives greatly reducing manufacturing costs compared to PS200. It is anticipated that PS300 has potential for sliding bearing and seal applications in both aerospace and general industry.
Effects of silver and group II fluoride solid lubricant additions to plasma-sprayed chromium carbide coatings for foil gas bearings to 650 C
Cas de paliers feuilles a gaz fonctionnant jusqu'a 650°C. Influence d'une addition de lubrifiant solide (argent et fluorures du groupe II) dans le revetement de carbure de chrome depose par pulverisation de plasma