PSI - Issue 42

Tereza Juhászová et al. / Procedia Structural Integrity 42 (2022) 1090–1097 Author name / Structural Integrity Procedia 00 (2019) 000–000

1096

7

(a)

(a)

Figure 5 Relation between stress intensity factor ratio and crack growth rate (a) and fitting of linear part of relation for Paris' equation(b)

Table 4 Paris' law constants for each specimen

Specimen

m [-] 5.697 5.556 4.832 4.816

C [mm/number of cycles·MPam 1/2 ]

R 2

0.901 0.895 0.915 0.923

E01 E02 A01 A02

1.868×10 -12 2.760×10 -12 2.669×10 -11 2.761×10 -11

0.949

5.592

2.562×10 -12

0.961

4.845

2.523×10 -11

7. Conclusion In this study, fatigue crack growth rate of stainless-steel specimens in three-point bending was investigated. Two productions of total 4 specimens were tested, under the same load and loading ratio R . Experimentally obtained data were evaluated by using 3D modelling in FEM software environment ANSYS. Relation between crack growth rate and stress intensity factor ratio was plotted in double logarithmic scale and the linear part was approximated by power function, which was used to determine Paris’ law constants for each specimen. The dispersion of the values for same productions does not show significant trend, although the results of European production shows higher values for constant m which could predict faster growth of discontinuities in those specimens. Acknowledgements The research was supported by the project No. 20-00761S of the Czech Science Foundation and by the project n.o. FAST-J-22-7959 of the Brno University of Technology internal grant agency.