TY - GEN
T1 - Creep strength and microstructure of AL20-25+Nb alloy sheets and foils for advanced microturbine recuperators
AU - Maziasz, Philip J.
AU - Shingledecker, John P.
AU - Evans, Neal D.
AU - Yamamoto, Yukinori
AU - More, Karren L.
AU - Trejo, Rosa
AU - Lara-Curzio, Edgar
AU - Stinner, Charles P.
PY - 2006
Y1 - 2006
N2 - The Oak Ridge National Laboratory (ORNL) and ATI Allegheny-Ludlum began a collaborative program in 2004 to produce a wide range of commercial sheets and foils of the new AL20-25+Nb stainless alloy, specifically designed for advanced microturbine recuperator applications. There is a need for cost-effective sheets/foils with more performance and reliability at 650-750°C than 347 stainless steel, particularly for larger 200-250 kW microturbines. Phase I of this collaborative program produced the sheets and foils needed for manufacturing brazed plated-fin (BPF) aircells, while Phase II provided foils for primary surface (PS) aircells, and modified processing to change the microstructure of sheets and foils for improved creep-resistance. Phase I sheets and foils of AL20-25+Nb have much more creep-resistance than 347 steel at 700-750°C, and foils are slightly stronger than HR120 and HR230. Preliminary results for Phase II show nearly double the creep-rupture life of sheets at 750°C/100 MPa, with the first foils tested approaching the creep resistance of alloy 625 foils. AL20-25+Nb alloy foils are also now being tested in the ORNL Recuperator Test Facility.
AB - The Oak Ridge National Laboratory (ORNL) and ATI Allegheny-Ludlum began a collaborative program in 2004 to produce a wide range of commercial sheets and foils of the new AL20-25+Nb stainless alloy, specifically designed for advanced microturbine recuperator applications. There is a need for cost-effective sheets/foils with more performance and reliability at 650-750°C than 347 stainless steel, particularly for larger 200-250 kW microturbines. Phase I of this collaborative program produced the sheets and foils needed for manufacturing brazed plated-fin (BPF) aircells, while Phase II provided foils for primary surface (PS) aircells, and modified processing to change the microstructure of sheets and foils for improved creep-resistance. Phase I sheets and foils of AL20-25+Nb have much more creep-resistance than 347 steel at 700-750°C, and foils are slightly stronger than HR120 and HR230. Preliminary results for Phase II show nearly double the creep-rupture life of sheets at 750°C/100 MPa, with the first foils tested approaching the creep resistance of alloy 625 foils. AL20-25+Nb alloy foils are also now being tested in the ORNL Recuperator Test Facility.
UR - http://www.scopus.com/inward/record.url?scp=33750832295&partnerID=8YFLogxK
U2 - 10.1115/GT2006-90195
DO - 10.1115/GT2006-90195
M3 - Conference contribution
AN - SCOPUS:33750832295
SN - 0791842401
SN - 9780791842409
T3 - Proceedings of the ASME Turbo Expo
SP - 225
EP - 236
BT - Proceedings of the ASME Turbo Expo 2006 - Power for Land, Sea, and Air
T2 - 2006 ASME 51st Turbo Expo
Y2 - 6 May 2006 through 11 May 2006
ER -