PSI - Issue 23

Jaroslav Polák et al. / Procedia Structural Integrity 23 (2019) 275–280 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

280

6

similar to cycling with dwells. However, the intensity of the damage was higher which is apparent from Manson Coffin curves (Fig. 2).

(b)

(a)

Fig. 7 . Cracked grain boundary after cycling with mechanical strain amplitude 3 × 10 -3 in in-phase thermomechanical cycle; (a) cracked grain boundary, (b) FIB cut showing oxidation and crack along the grain boundary.

Table 1. Parameters of the Manson-Coffin law in three types of cycling. Parameters  f ´ c constant strain rate cycling 0.211 -0.649 constant strain rate cycling with dwells 0.032 -0.452 thermomechanical in-phase cycling 0.619 -0.952

Acknowledgements

The present work was conducted in the frame of IPMinfra supported through project No. LM2015069 and the project CEITEC 2020 No. LQ1601 of MEYS. The support by the project RVO: 68081723 and by grants 13-23652S and 15-08826S of GACR is gratefully acknowledged.

References

Polák, J., Petráš, R., Heczko, M., Kuběna, I., Kruml, T., Chai, G., 2014. Low cycle fatigue behavior of Sanicro25 steel at room and at elevated temperature. Materials Science and Engineering A 615, 175-182. Polák, J., Petráš, R., Chai, C. , Škorík, V., 2016. Surface profile evolution and fatigue crack initiation in Sanicro 25 steel at room temperature, Materials Science and Engineering 658, 221-228. Mazánová, V., Heczko, M., Polák , J., 2018. Fatigue crack initiation and growth in 43Fe-25Ni-22.5Cr austenitic steel at a temperature of 700 degrees C, International Journal of Fatigue 114, 11-21. Li, H.B., Jing, H., Xu, L. et al., 2019. Life, dislocation evolution, and fracture mechanism of a 41Fe-25.5Ni-23.5Cr alloy during low cycle fatigue at 700°C, International Journal of Fatigue 119, 20-33. Petráš, R. , Škorík, V. , Polák J., 2016 . Thermomechanical fatigue and damage mechanisms in Sanicro 25 steel, Materials Science and Engineering 650, 52-62.