- Additional Authors
- Description
- 17 p. : ill.
- Summary
- "Fatigue life at elevated temperatures is often shortened by oxidation. Grain boundary oxidation penetrates deeper than the surface oxidation. Therefore, grain boundary oxide penetration could be the primary cause of accelerated fatigue crack nucleation and propagation, and the shortened fatigue life at elevated temperatures. Grain boundary oxidation kinetics was studied and its statistical scatter was analyzed by the Weibull's distribution function. The effects of grain boundary oxidation on shortened fatigue life was analyzed and discussed. A model of intermittent microruptures of the grain boundary oxide was proposed for the fatigue crack growth in the low frequency region. The proposed model is consistent with the observations that fatigue crack growth rate in the low frequency region with hold time at K sub max is inversely proportional to cyclic frequency and that crack growth is intergranular."--NTIS abstract.
- Series Statement
- NASA contractor report ; 175050
- Uniform Title
- NASA contractor report ; NASA CR-175050.
- Subject
- Note
- "January 1986."
- Sponsored in part by the Host Program. Presented at the Minnowbrook Conference on Life Prediction for High Temperature Gas Turbine Materials, Blue Mountain Lake, N.Y., 27-30 Aug. 1985.
- Bibliography (note)
- Includes bibliographical references (p. 10-11).
- Additional Formats (note)
- Distributed to depository libraries in microfiche; also available via the Internet.
- Reproduction (note)
- Funding (note)
- Prepared for Lewis Research Center under grant
- Call Number
- GPO Microfiche NAS 1.26:175050
- OCLC
- marcive237004522
- Author
Liu, H. W. (Hao Wen), 1926-
- Title
Grain boundary oxidation and oxidation accelerated fatigue crack nucleation and propagation [microform] / H.W. Liu and Yoshiki Oshida ; [performing organization: Syracuse University, Dept. of Mechanical and Aerospace Engineering ; sponsoring agency: National Aeronautics and Space Administration].
- Imprint
Syracuse, N.Y. : Syracuse University, Dept. of Mechanical and Aerospace Engineering ; [Cleveland, Ohio] : National Aeronautics and Space Administration, Lewis Research Center ; Springfield, Va. : National Technical Information Service, distributor, [1986]
- Series
NASA contractor report ; 175050
NASA contractor report ; NASA CR-175050.
- Additional Formats
Distributed to depository libraries in microfiche; also available via the Internet.
- Bibliography
Includes bibliographical references (p. 10-11).
- Funding
Prepared for Lewis Research Center under grant NAG 3-348 533-04-1 2
- Reproduction
Microfiche. [Washington, D.C. : National Aeronautics and Space Administration], 1986. 1 microfiche : negative.
- Indexed Term
Grain boundaries; Oxidation; Crack propagation; Fatigue (Materials); Microstructure; Nucleation; Distribution functions; Low frequencies
- Added Author
Oshida, Yoshiki.
Syracuse University. Department of Mechanical and Aerospace Engineering.
Lewis Research Center.
Conference on Life Prediction for High-Temperature Gas Turbine Materials (1985 : Syracuse, N.Y.)
- Other Form:
Print version: Liu, H. W. (Hao Wen), 1926- Grain boundary oxidation and oxidation accelerated fatigue crack nucleation and propagation. (OCoLC)795577606
Online version: Liu, H. W. (Hao Wen), 1926- Grain boundary oxidation and oxidation accelerated fatigue crack nucleation and propagation. (OCoLC)795581101
- Gpo Item No.
0830-H-14 (MF)
- Sudoc No.
NAS 1.26:175050