A general model to predict the elastic-plastic stress distribution and fracture strength of notched bars in plane strain bending

Analysis of notch effect in the apparent fracture toughness and the fracture micromechanisms of ferritic–pearlitic steels operating within their lower shelf

“…-L values seem to be very low, but the same order of magnitude has been reported [11] [11,28,29] presents similar results in other steels. Wilshaw [28] found that L and d are equal, whereas for Yokobori [29] the relation gave L=1.2d for the same material subjected to different heat treatments, and then, presenting different grain sizes.…”

“…Wilshaw [28] found that L and d are equal, whereas for Yokobori [29] the relation gave L=1.2d for the same material subjected to different heat treatments, and then, presenting different grain sizes.…”

Statistical analysis of cleavage fracture ahead of sharp cracks and rounded notches

“…Ahead of a rounded notch (with root radius large compared to microstructural dimensions), this process has been considered to occur when the maximum value of the local tensile stress exceeds a critical fracture stress (14), generally regarded as a quantity independent of temperature and strain rate (14,15). For loads wel 1 below general yield, the location of the peak stress ahead ..…”

On the Line Method apparent fracture toughness evaluations: Experimental overview, validation and some consequences on fracture assessments

“…Such a ratio, also known as the Neuber number [36] was proposed by Madrazo et al [6] as a tentative criterion to limit the validity of the LM (and PM) apparent fracture predictions, given that it was observed that this fracture parameter tended to remain constant in Al7075-T651 for ρ/L>100. This was also related to the shift from plane strain conditions to the plane stress onset when the notch radius increases, following the arguments provided by Taylor [9] to explain the experimental observations obtained by Irwin [37], Tsuji et al [38], Wilshaw et al [39], and Yokobori and Konosu [40]. The 555 results gathered here do not reveal any weakening of the notch effect, with a continuous increase of the apparent fracture toughness for ρ/L values as high as 714 (steel S460M at -140ºC), and 112 tests with ρ/L ratio values higher than 100.…”

“…In some cases a critical radius has been found below which the notch effect is negligible [39,40], whereas in other cases such a critical radius has not been detected [6,38]. On some occasions, the apparent fracture toughness remains approximately constant above a certain notch radius [6,9,39], and the experimental results differ from the LM or PM predictions (which predict a monotonically increasing fracture resistance when increasing the notch radius), whereas in other cases the experimental results continuously increase with the notch radius [9,38,40]. Some results of the apparent fracture toughness are conservative [2,9], whereas the predictions for other cases perfectly fit the experimental results or are non-conservative [3,6,9].…”