TY - GEN
T1 - Evaluation of alumina-forming austenitic foil for advanced recuperators
AU - Pint, Bruce A.
AU - Brady, Michael P.
AU - Yamamoto, Yukinori
AU - Santella, Michael L.
AU - Maziasz, Philip J.
AU - Matthews, Wendy J.
PY - 2010
Y1 - 2010
N2 - A corrosion- and creep-resistant austenitic stainless steel has been developed for advanced recuperator applications. By optimizing the Al and Cr contents, the alloy is fully austenitic for creep strength while allowing the formation of a chemically-stable external alumina scale at temperatures up to 900°C. An alumina scale eliminates long-term problems with the formation of volatile Cr oxy-hydroxides in the presence of water vapor in exhaust gas. As a first step in producing foil for primary surface recuperators, three commercially cast heats have been rolled to ∼100μm thick foil in the laboratory to evaluate performance in creep and oxidation testing. Results from initial creep testing are presented at 675° and 750°C showing excellent creep strength compared to other candidate foil materials. Laboratory exposures in humid air at 650°-800°C have shown acceptable oxidation resistance. Similar oxidation behavior was observed for sheet specimens of these alloys exposed in a modified 65kW microturbine for 2,871h. One composition that showed superior creep and oxidation resistance has been selected for preparation of a commercial batch of foil.
AB - A corrosion- and creep-resistant austenitic stainless steel has been developed for advanced recuperator applications. By optimizing the Al and Cr contents, the alloy is fully austenitic for creep strength while allowing the formation of a chemically-stable external alumina scale at temperatures up to 900°C. An alumina scale eliminates long-term problems with the formation of volatile Cr oxy-hydroxides in the presence of water vapor in exhaust gas. As a first step in producing foil for primary surface recuperators, three commercially cast heats have been rolled to ∼100μm thick foil in the laboratory to evaluate performance in creep and oxidation testing. Results from initial creep testing are presented at 675° and 750°C showing excellent creep strength compared to other candidate foil materials. Laboratory exposures in humid air at 650°-800°C have shown acceptable oxidation resistance. Similar oxidation behavior was observed for sheet specimens of these alloys exposed in a modified 65kW microturbine for 2,871h. One composition that showed superior creep and oxidation resistance has been selected for preparation of a commercial batch of foil.
UR - http://www.scopus.com/inward/record.url?scp=82055161273&partnerID=8YFLogxK
U2 - 10.1115/GT2010-23003
DO - 10.1115/GT2010-23003
M3 - Conference contribution
AN - SCOPUS:82055161273
SN - 9780791844007
T3 - Proceedings of the ASME Turbo Expo
SP - 487
EP - 494
BT - ASME Turbo Expo 2010
T2 - ASME Turbo Expo 2010: Power for Land, Sea, and Air, GT 2010
Y2 - 14 June 2010 through 18 June 2010
ER -