Crack Paths 2006

found. This morphology has been observed in all the examined series (Figures 9-12)

[14-15].

Figure 8: cracks nucleation at the notch tip.

During the test, the crack propagates through the pores and often some secondary non

propagating cracks nucleate from the pores themselves.

a) b) Figure 9: crack path during propagation (a) and secondary non propagating cracks (b)

Figure 10:

/ d N d a

] / [ 1 0 7 cyclem |

Figure 12: ] / [ 1 0 3 9 cyclem d N d a ˜ |