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A FATIGUE‐CRACK‐GROWTH‐BASED ANALYSIS OF TWO‐STEP CORROSION FATIGUE TESTS
Author(s) -
Ishihara S.,
McEvily A. J.,
Shiozawa K.
Publication year - 1995
Publication title -
fatigue and fracture of engineering materials and structures
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.887
H-Index - 84
eISSN - 1460-2695
pISSN - 8756-758X
DOI - 10.1111/j.1460-2695.1995.tb00857.x
Subject(s) - corrosion fatigue , materials science , structural engineering , paris' law , corrosion , crack closure , alloy , aluminium , fatigue testing , fracture mechanics , metallurgy , composite material , engineering
A method for the analysis of two‐step fatigue level sequences is proposed and compared with experimental results. Two‐step loading tests of the aluminum alloy 2017‐T4 in 3% sodium chloride solution have been carried out in conjunction with a replica technique used to monitor the growth of fatigue cracks. Fatigue cracks were nucleated at corrosion pits 10–15 μm in size, and crack growth rather than crack initiation was found to take up the major portion of the fatigue lifetime in these tests. The results could therefore be analyzed on the basis of the following constitutive relation for fatigue crack growth. d a /d N = A (Δ K eff ‐Δ K effth ) 2 This analysis was simplified since the influence of transients in the crack growth rate induced upon change in load level was found to be minimal. The approach provides a rational basis for dealing with load‐sequence effects.