Development of Creep-Resistant, Alumina-Forming Ferrous Alloys for High-Temperature Structural Use

Conference · Tue May 01 04:00:00 EDT 2018 · ASME Proceedings, Elevated Temperature Design Methods

DOI:https://doi.org/10.1115/ETAM2018-6727· OSTI ID:1454397

Yamamoto, Yukinori ^[1]; Brady, Michael P. ^[1]; Muralidharan, Govindarajan ^[1]; Pint, Bruce A. ^[1]; Maziasz, Philip J. ^[1]; Shin, Dongwon ^[1]; Shassere, Benjamin ^[1]; Babu, Sudarsanam Suresh ^[1]; Kuo, Chih-Hsiang ^[1]

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1. ORNL

This paper overviews recent advances in developing novel alloy design concepts of creep-resistant, alumina-forming Fe-base alloys, including both ferritic and austenitic steels, for high-temperature structural applications in fossil-fired power generation systems. Protective, external alumina-scales offer improved oxidation resistance compared to chromia-scales in steam-containing environments at elevated temperatures. Alloy design utilizes computational thermodynamic tools with compositional guidelines based on experimental results accumulated in the last decade, along with design and control of the second-phase precipitates to maximize high-temperature strengths. The alloys developed to date, including ferritic (Fe-Cr-Al-Nb-W base) and austenitic (Fe-Cr-Ni-Al-Nb base) alloys, successfully incorporated the balanced properties of steam/water vapor-oxidation and/or ash-corrosion resistance and improved creep strength. Development of cast alumina-forming austenitic (AFA) stainless steel alloys is also in progress with successful improvement of higher temperature capability targeting up to ~1100°C. Current alloy design approach and developmental efforts with guidance of computational tools were found to be beneficial for further development of the new heat resistant steel alloys for various extreme environments.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Fossil Energy (FE)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1454397
• Conference Information: Journal Name: ASME Proceedings, Elevated Temperature Design Methods
• Country of Publication: United States
• Language: English