PSI - Issue 23

Tomáš Babinský et al. / Procedia Structural Integrity 23 (2019) 523–528 Babinský & Pol ák / Structural Integrity Procedia 00 (2019) 000 – 000

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dislocations in 713LC are forced to group into superdislocations earlier during the cycling. Cyclic plastic response of Rene 41 is alike a one-phase material as it shows no minor peaks in the second derivatives.

Table 2. Values of effective moduli and effective stresses of γ and γ ’ phases in the first cycle. Alloy Half-loop E eff [GPa] σ e, γ [MPa]

σ e, γ ’ [MPa]

IN713LC

Tensile

203 216 203 204

~90

~340 ~350

Compressive

Rene 41

Tensile

~210 ~170

Compressive

5. Conclusions

The analysis of low-cycle fatigue tests performed on 713LC and Rene 41 alloys led to following conclusions:

 Analysis of the hysteresis loop shape using statistical theory is an effective tool for a description of the cyclic plastic response of a material.  Cyclic slip is localized into PSBs. Consequently, the internal stress component is lowered which is depicted as a drop of global maximum in a plot of second derivatives vs. fictive stress.  Casting defects and a dendritic structure of 713LC led to premature fracture.  Cyclic plastic response of Rene 41 has a character similar to one-phase material.

Acknowledgements

The present work was conducted in the frame of IPMinfra supported through project No. LM2015069, the project CEITEC 2020 No. LQ1601 of MEYS and the project CEITEC-VUT-J-19-5923. The support by the project RVO:68081723 and by grants 13-23652S and 15-08826S of GACR is gratefully acknowledged.

References

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