PSI - Issue 61

İmren Uyar et al. / Procedia Structural Integrity 61 (2024) 195 – 205 İ. Uyar, E. Gürses / Structural Integrity Procedia 00 ( 2019) 000 – 000

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(a) (b) Fig. 6. Normalized concentration distribution of fiber with (a) central crack, (b) arc crack

It is also essential that if the crack fails to initiate propagation at the point of maximum concentration difference (i.e., where the outer concentration is highest), it remains inactive and does not propagate in subsequent instances. In such cases, when the surface of the fiber is exposed to a constant maximum ionic concentration, ions diffuse the inner part of the fiber, and relaxation processes begin. Fig. 7 compares the concentration distribution between the center and radial arc cracks after crack growth. The non-contact surface area increases the shielding effect when the crack occurs close to the outer surface. Fig.8 shows that the phase field distributions after crack propagation and just before the crack reaches the fiber surface.

Fig. 7. Normalized concentration distribution of fiber after crack growth with (a) central crack, (b) arc crack

Fig. 8. Phase field distribution of fiber with (a) central crack, (b) surface crack