NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
The effect of microstructure on 650 C fatigue crack growth in P/M AstroloyThe effect of microstructure on fatigue crack propagation at 650 C has been studied in a P/M nickel-base superalloy, Astroloy. Crack propagation data were obtained in air and vacuum at 20 cpm with a modified compact tension specimen. The rate of crack growth, da/dn, was correlated with the stress intensity range. Key microstructural variables examined were grain size and the distribution and size of the strengthening gamma prime phase. A fine grain size less than 20 microns always promoted rapid, intergranular failure, while a large grain size promoted slower, transgranular failure which decreased as the size and volume fraction of aging gamma prime was manipulated so as to increase alloy strength. The rapid, intergranular mode of failure of the fine grain microstructures was suppressed in vacuum.
Document ID
19840029608
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Gayda, J.
(NASA Lewis Research Center Cleveland, OH, United States)
Miner, R. V.
(NASA Lewis Research Center Cleveland, OH, United States)
Date Acquired
August 12, 2013
Publication Date
November 1, 1983
Publication Information
Publication: Metallurgical Transactions A - Physical Metallurgy and Materials Science
Volume: 14A
ISSN: 0360-2133
Subject Category
Metallic Materials
Accession Number
84A12395
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available