Journal of Power System Engineering (동력기계공학회지)
- Volume 8 Issue 4
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- Pages.11-16
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- 2004
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- 2713-8429(pISSN)
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- 2713-8437(eISSN)
The Effect on Fatigue Crack Growth due to Omitting Low-amplitude Loads from Variable Amplitude Loading
변동하중에서 미소하중의 제거가 균열진전에 미치는 영향
초록
In this study, to investigate the effects of omitting low-amplitude cycles from a flight-simulation loading, crack growth tests were conducted on 2124-T851 aluminum alloy specimens. Three test spectra were generated by omitting small load ranges as counted by the rain-flow count method. The crack growth test results were compared with the data obtained from the flight-simulation loading. The experimental results show that the ranges equal to or smaller than 5% of the maximum load do not contribute to crack growth behavior because these are below the initial stress intensity factor range. Omitting these from the flight-simulation loading, test time can be reduced by 54%. However, in the case of omitting the load ranges below 15% of the maximum load, crack growth rates decreased, and crack growth curve deviated from the crack growth data under the flight-simulation loading because loading cycles above fatigue fracture toughness were omitted.
키워드