PSI - Issue 28

Stepan Major et al. / Procedia Structural Integrity 28 (2020) 561–576 Author name / Structural Integrity Procedia 00 (2019) 000–000

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local brittle crack created a connection to the surface and presence of gas atmosphere caused changes in crack growth mechanism. From this moment is crack growth process same as in the case of cracks generated on the sample surface.

Fig. 10. Nitrided specimens and spatial orientation of the surface elements at the macroscopic level (square network - a 99 = 99 μm): (a) loading ratio L R = 0; (b) loading ratio L R = 0.27; (c) loading ratio L R = 0.5; (d) loading ratio L R = 0.73; (e) loading ratio L R = 1.