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| Failure Mechanisms | ||||||||||||||||||||
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Three
crack growth regions exist: Region A, No crack growth; Region B, Linear
Growth on a Log/Log Plot; Region C, Unstable growth, critical size crack.
· From the growth rate in region B, assuming that the initial crack size is a, and the critical crack size is c, the time for crack growth between these limits approximates the Fatigue Life. |
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| From: Suresh, "Fatigue of Materials," Cambridge (1991) | ||||||||||||||||||||
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Using:
(da/dN) = A ΔKm
= A Δσm
am/2,
dN = da / am/2 {B Δσm} , so that: |
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