Gas turbine engine oil additives for advanced bearings - advanced steels

Eleven additives from Phase I show feasibility to substantially improve the lubrication of corrosion resistant bearing steels for JSF and other jet engine bearings and gears. Feasibility tests covered scuffing and wear performance. Phase II addresses coking, oxidation and material compatibility issues in addition to tribology performance. A strategic plan for coking, compatibility and tribology tests will screen Phase I additives and allow formulation changes to meet all requirements. Phase II additives will likely be formulated for a different viscosity grade according to an Air Force initiative to establish an optimum viscosity grade for new and legacy propulsion hardware. Extensive screening of the new formulations will be conducted to assure performance in 40 mm bearing tests and a T63 engine test for a selected oil formulation. Tribology tests include surface initiated fatigue, rolling contact fatigue, oil-out performance and tribology performance mapping for wear and scuffing. This project is supported by three major oil companies, two major additive suppliers and small businesses. The proposed work is part of a technology plan for the Air Force VAATE I program with the goal of F135 engine demonstrator testing following the completion of Phase II.