Fatigue crack initiation at a notch

Strain-based modeling of fatigue crack growth – An experimental approach for stainless steel

“…This means that the fatigue life assessment for designing can be replaced with the crack growth prediction. Extensive attempts have been made to estimate the fatigue life by integrating the crack growth [16][17][18][19][20][21]. However, most of these approaches were made by using the SIF.…”

Experimental investigation and numerical prediction of fatigue crack growth of 2024-T4 aluminum alloy

“…9(a) summarizes the fatigue crack growth results of CT specimens under constant amplitude loading in the log(DK) À log(da/dN) representation. Because no pre-cracks were used in the fatigue crack growth experiments, the significant influence of the notch geometry is obviously reflected by the early stage of crack growth [9,[41][42][43][44]. After the fatigue crack propagates out of the notch-affected zone, the stabilized fatigue crack growth is achieved as expected.…”

Effect of cold expansion on improving of fatigue initiation life in Aluminium alloy

“…This ratio increases with increasing of stress ratio and vary from 3.22 to 3.85. Also, the increasing in stress ratio increases the initiation life [19] that is attributed to reduction in amplitude loading. The predicted results have exponential evolution and are given by equation 9 and 10 respectively for expanded hole and drilled hole (without residual stress).…”

“…It is noticed that an increase in the R-ratio decreases the number of cycles to initiate a fatigue crack. In study conducted by Ranganathan et al [19], crack initiation phase has been considered in the estimation of total fatigue life when short crack growth approach has been applied. The results on fatigue crack initiation of 2024 T351 Al-alloy shows an increasing in initiation life with increasing in stress ratio and maximum remote stress in absence of residuals stresses.…”