Microstructure investigations of Pt-modified gamma '-Ni3Al + gamma-Ni coatings on Ni-based superalloys

TitleMicrostructure investigations of Pt-modified gamma '-Ni3Al + gamma-Ni coatings on Ni-based superalloys
Publication TypeJournal Article
Year of Publication2010
AuthorsCao GH, Ou TP, Jiang H, Russell AM
Journal TitleJournal of Materials Research
Volume25
Pages1191-1195
Date Published06/01
ISBN Number0884-2914
Accession NumberISI:000278161900025
Keywordsbond coat, hot corrosion, mu-phase, ni-based superalloys, nickel-base superalloy, niptal coatings, OXIDATION BEHAVIOR, platinum, precipitation, THERMAL BARRIER COATINGS
Abstract

The microstructure of Pt-modified gamma'-Ni3Al + gamma-Ni coating on CMSX-4 single-crystal superalloy has been investigated by transmission electron microscopy (TEM). Cross-sectional TEM analyses showed the presence of precipitates in the coating. This precipitate was identified as the hexagonal topologically close-packed (TCP) mu phase with lattice parameters a = 0.473 nm and c = 2.565 nm. The energy-dispersive x-ray (EDX) spectrum of the mu phase suggested a refractory element rich compound comprising the elements Re, W, and Co. Twin domains parallel to (001) were found in the mu phase. The mechanisms of the mu phase and twinning formation were discussed.

URL<Go to ISI>://000278161900025
DOIDoi 10.1557/Jmr.2010.0148