PSI - Issue 38

Paul Catalin Ilie et al. / Procedia Structural Integrity 38 (2022) 271–282 P. C. Ilie et al./ Structural Integrity Procedia 00 (2021) 000 – 000

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Fig. 2. (a) Semi Elliptical Crack; (b) Embedded Elliptical Crack; (c) Corner Crack .

For simplicity only the  K I equations used in the analytical models implemented in MATLAB are shown below: Semi-elliptical crack [7]: ∆ = (∆ )√ ( , , , ) (2)

Embedded elliptical crack [7]:

(3) (4)

∆ = ∆ √ ∆ = ∆ √

Corner (quarter elliptical) crack [8]:

Where is the geometry correction factor and = 1 + 1.464 ( ) 1.65 . Crack growth increments of and at crack front points (i.e. the deepest crack front, A and surface crack front, C) are then numerically carried out on the basis of the analytical model with applied loading cycles to compute fatigue crack propagation life of a-N results as formulated in Eq. (5) [17].