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| Failure Mechanisms | |||||||||||||||||
| Random
Loading
· In
most real fatigue situations the periodic stress amplitude is not constant
during component use.
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| From: Callister, "Materials Science & Engineering," Wiley (1994) | |||||||||||||||||
| damage"
has been developed to estimate fatigue life under these conditions.
· For a stress amplitude Δσithenumber of cycles to failure is NI . · If the sample experiences nj cycles at this stress amplitude, it accumulates a fractional damage: (nj / NI ). Damage histories of this type are then summed to obtain the total life of the sample. |
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