Issue 62

Yu. G. Matvienko et alii, Frattura ed Integrità Strutturale, 62 (2022) 541-560; DOI: 10.3221/IGF-ESIS.62.37

e

f

g Figure 8: Dependencies of maximum circumferential strain at the hole edge versus remote stress level for the following cycles of loading: the first (a), the second (b), 14th (c), 115th (d), 1316th (e), 2927th (f), and 3530th (g) loading cycles.

Cicles number, N

1 0

2

14

115 4.75 9.48

735 6.60 9.10

1316 7.18 8.68 –4.15 12.83

2927 8.00 9.22 –3.62 12.84

3530 8.17 10.65 –3.81 14.46

0.69 9.54

2.64 9.52

ln N

   3 10 A MAX x  3 10 A MIN x  

11.90 –1.45 13.35

–2.87 12.41

–3.56 13.08

–3.50 12.98

–3.80 12.90

   3 10 A x

Table 5: Local deformation parameters, obtained at different stages of low-cycle fatigue:   A MAX x

 A MIN x

is maximal local strain; 

is

  A x is strain range referred to the critical point A at the boundary of the filled hole.

minimal local strain;

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