Della Corte, C., Valco, M.J., Radil, K.L. and Heshmat, H. “Performance and Durability of High Temperature Foil Air Bearings for Oil-Free Turbomachinery,” (2000) Tribology Transactions, Volume 43 (4), pp. 774-780.
The performance and durability of advanced, high temperature foil air bearings are evaluated under a wide range (10 to 50 kPa) of loads at temperatures from 25 to 650ºC. The bearings are made from uncoated nickel based superalloy foils. the foil surface experiences sliding contact with the shaft during initial start/stop operation. To reduce friction and wear, the solid lubricant coating, PS304, is applied to the shaft by plasma spraying. PS 304 is a NiCr based Cr2O3 coating with silver and barium fluoride/calcium fluoride solid lubricant additions.