The solidification metallurgy of Alloy 718 and other Nb-containing superalloys

Conference · Sun Jan 01 00:00:00 EST 1989

DOI:https://doi.org/10.7449/1989/Superalloys_1989_59_68· OSTI ID:6002002

Cieslak, M. J.; Knorovsky, G. A.; Headley, T. J.; Romig, Jr., A. D.

The solidification behavior of Alloy 718 and other Nb-bearing austenitic superalloys has been examined using an integrated analytical approach. All alloys of this type begin solidification with the formation of Nb-lean austenitic dendrites. Interdendritic eutectic-type solidification constituents involving MC-type carbides and a Nb-rich Laves phase occur in these alloys. The ..gamma../Laves eutectic constituent terminates solidification in these alloys. Nb is the dominant element in the evolution of solidification microstructure with C and Si affecting the amounts of ..gamma../MC and ..gamma../Laves constituent observed. Simple solidification models predict reasonably well the amount of eutectic constituent observed. 11 refs., 9 figs., 2 tabs.

• Research Organization: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 6002002
• Report Number(s): SAND-89-0264C; CONF-890646-1; ON: DE89008196
• Resource Relation: Conference: International symposium on alloy 718 metallurgy and applications, Pittsburgh, PA, USA, 12 Jun 1989; Other Information: Portions of this document are illegible in microfiche products
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
IRON ALLOYS
SOLIDIFICATION
NICKEL ALLOYS
NIOBIUM ALLOYS
CARBIDES
CASTING
DENDRITES
EUTECTICS
LAVES PHASES
MICROSTRUCTURE
SCANNING ELECTRON MICROSCOPY
WELDING
ALLOYS
CARBON COMPOUNDS
CRYSTAL STRUCTURE
CRYSTALS
ELECTRON MICROSCOPY
FABRICATION
JOINING
MICROSCOPY
PHASE TRANSFORMATIONS
360102* - Metals & Alloys- Structure & Phase Studies
360101 - Metals & Alloys- Preparation & Fabrication