SBIR-STTR Award

Several advanced solid film lubricant coating processes are evaluated to be used for turbopump gears operating at high speeds and high contact pressures in an RL-10 rocket engine at cryogenic temperatures. Based on existing application data concerning the performance of the proposed advanced coatings a significant improvement in turbopump gear operation is expected. Improvements in coating uniformity, structure, wear life with a reduction in friction and vibrations yield improved turbopump operations. This study details specific characterization and cryogenic testing at appropriate loads and speeds similar to that of rocket fuel pump. Characterization includes microscopy, metallurgy and surface characterization. Cryogenic WAM testing is used to provide the proper tribological test conditions. Coating compatibility with liquid hydrogen is investigated. Advanced coatings include PVD, Spray, Burnish and Smart Surface Laser Textured solid film lubes and Soft Metallic coatings by PVD and Hybrid PVD. We deliver a reference database of the various coating properties and test results of the surface treatments as well as recommendations for treatment of the RL-10 turbopump gear based on our results with deliberate concern for economic industrial viability. Additionally we deliver a robust storage method for treated samples and gears which insures full protection from terrestrial coating degradation primarily caused by oxidation during storage, pre-assembly and ground transportation

Our advanced surface engineering technologies provide new and broader operating windows for moving mechanical parts in extreme environments. Several of our advanced solid film lubricant coating technologies have been successfully evaluated as viable candidates for RL-10 rocket engine turbopumps. The turbomachinery used for rocketry operate under extreme conditions with a zero fault tolerance. Gears and bearings operate at high speeds and high contact pressures at cryogenic temperatures. Based on our Phase I results a significant improvement in turbopump operation is possible. Improvements in coating uniformity, structure, wear life with a reduction in friction and vibrations yield improved turbopump operations. This study details specific cryogenic testing and laboratory characterization at appropriate loads and speeds similar to that of rocket fuel pump. Cryogenic WAM testing is used to provide the proper tribological test conditions. Coating compatibility with liquid propelent is investigated. Advanced coatings include PVD, Spray, Burnish and Smart Surface Laser Textured solid film lubes and Soft Metallic coatings by PVD and Hybrid PVD. We deliver a reference database of our advanced surface engineering treatments as well as surface treatment of the RL-10 bearing sleeve and turbopump gear based on our results with deliberate concern for economic industrial viability. We provide a compiled matrix of tribological solutions to choose from based on operational level requirements. By working closely with Pratt & Whitney during our Phase I effort and as well as during this research project on technical issues and risk analysis we shall do our first engine test third quarter of 2006 on a bearing sleeve, followed by further engine testing with our new technology on turbopump gears. An incremental approach for insertion of our technology in to full production requires a well executed project flow from Research to Development to PWA Certified Production. We shall also work with Pratt Whitney for process certification.

Keywords:
Lubrication, Tribology, Friction, Wear, Cryogenic, Turbomachinery, Smart-Surfaces, Coatings