Recognition of Ae Signals from Fatigue-cracked and Patch-repaired Aluminum Panel
نویسندگان
چکیده
The fatigue crack growth behavior of a cracked and patch-repaired AA2024-T3 panel has been monitored by acoustic emission (AE). It was found that the overall crack growth rate was reduced and the crack propagation into the adjacent rivet hole was also retarded by introducing the patch repair. AE signals due to crack growth after the patch repair and those due to disbonding of the aluminum-patch interface were discriminated each other by using principal component analysis. The former showed higher center frequency and lower amplitude, whereas the latter showed longer rise time, lower frequency and higher amplitude. This type of signal recognition method can be effectively used for the prediction of fatigue crack growth behavior of the patch-repaired structures, with the aid of a nontraditional AE source location.
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