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The effect of material heterogeneity and random loading on the mechanics of fatigue crack growthThis paper reviews experimental work on the influence of variable amplitude or random loads on the mechanics and micromechanisms of fatigue crack growth. Implications are discussed in terms of the crack driving force, local plasticity, crack closure, crack blunting, and microstructure. Due to heterogeneity in the material's microstructure, the crack growth rate varies with crack tip position. Using the weakest link theory, an expression for crack growth rate is obtained as the expectation of a random variable. This expression is used to predict the crack growth rates for aluminum alloys, a titanium alloy, and a nickel steel in the mid-range region. It is observed, using the present theory, that the crack growth rate obeys the power law for small stress intensity factor range, and that the power is a function of a material constant.
Document ID
19860042204
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Srivatsan, T. S.
(Atlanta Univ. GA, United States)
Sambandham, M.
(Atlanta Univ. GA, United States)
Bharucha-Reid, A. T.
(Atlanta University Georgia)
Date Acquired
August 12, 2013
Publication Date
January 1, 1985
Subject Category
Structural Mechanics
Accession Number
86A26942
Funding Number(s)
CONTRACT_GRANT: NAG1-413
CONTRACT_GRANT: DAAG29-83-G-0116
Distribution Limits
Public
Copyright
Other

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