Steam Turbine Materials and Corrosion. DOE/NETL-IR-2006-116

摘要

Ultra supercritical (USC) power plants offer the promise of higher efficiencies and lower emissions. Current goals of the U.S. Department of Energys Advanced Power Systems Initiatives include coal generation at 60% efficiency, which would require steam temperatures of up to 760 degrees C. This research examines the steamside oxidation of alloys for use in USC systems, with emphasis placed on applications in high- and intermediate-pressure turbines. The list of alloys being examined is discussed, including the addition of new alloys to the study. These include alloy 625, selected because of its use as one of the two alloys used for turbine rotors, valves, casings, blading and bolts in the European AD700 full-scale demonstration plant (Scholven Unit F). The other alloy, alloy 617, is already one of the alloys currently being examined by this project. Other new alloys to the study are the three round robin alloys in the UK-US collaboration: alloys 740, TP347HFG, and T92. Progress on the project is presented on cyclic oxidation in 50% air 50% water vapor, furnace exposures in moist air, and thermogravimetric analysis in argon with oxygen saturated steam.