Aluminum alloy 2524 and laser melting deposited TC11 titanium alloy were selected for the Fatigue Crack Growth (FCG) tests under different load conditions, Digital Image Correlation (DIC) method is adopted to obtain the Crack Tip Opening Displacement (CTOD) during FCG, the variations of CTOD, the range of CTOD, the plastic component of CTOD and the area of CTOD hysteresis loop in FCG are investigated. Meanwhile, the relationships between Fatigue Crack Growth Rate (FCGR) and these parameters are further analyzed, and a FCGR model based on the area of CTOD hysteresis loop is proposed. The results show that correspondences between the area of CTOD hysteresis loop and FCGR, as well as between the plastic component of CTOD and FCGR, are clearly revealed under different stress ratios and material orientations, which indicate these two mechanical parameters can effectively characterize the influence of plastic behavior in FCG. The results also indicate that the area of CTOD hysteresis loop is applicable for both constant amplitude and variable amplitude loading conditions, and less affected by accidental measurement errors, which has certain advantages in practical applications.
WANG Qiuyi
,
WU Yanzeng
,
BAO Rui
. Analysis on CTOD corresponding parameters during fatigue crack growth[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2022
, 43(6)
: 526632
-526632
.
DOI: 10.7527/S1000-6893.2022.26632
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