Fretting Wear Resistant Thermal Spray Coatings for Titanium Alloy Components

Bearing housings and flanges in propulsion systems experience excessive fretting wear on the titanium alloy surface due to adverse vibrations, loads, and temperature cycling.  Traditionally, fretting wear problems are solved using steel inserts or bushings that are press-fit into the titanium alloy casing and interface with the bearings.  In order to reduce the weight and avoid unnecessary steel-titanium couplings, it is proposed to replace the inserts with surface coating technologies that will provide fretting resistance and will not affect the bulk mechanical characteristics of the components.  Thus, in this Phase I SBIR program, PTI will demonstrate the feasibility of a fretting wear resistant thermal spray transition coating followed by subsequent surface finishing to eliminate fretting wear at the surface of titanium alloys for the application to components and flanges of the LiftFan system.   BENEFIT: Successful development of the fretting wear resistant coating system will benefit the aerospace industry by extending the life of many components currently affected by fretting wear. Subsequent to implementation onto components of the F-35 Joint Strike Fighter, PTI will market the technology to the multi-billion dollar turbine engine industry as well as other industries requiring fretting wear resistance technology.