Interaction of fatigue and creep in MAR-M 247 superalloy

Lifetime of MAR-M 247 Ni-based superalloy was experimentally studied under high-frequency cyclic loading (120 Hz) with constant tensile mean stress m = 300 MPa at temperature 900 °C in air. The stress amplitude a was changed in order to investigate the superalloy lifetime in a wide range of conditions, from pure creep to pure fatigue. The superposition of the stress amplitude on the mean stress does not influence the specimen lifetime until a threshold value is reached. Scanning electron microscopy was utilized for the fracture surface observation with the aim to identify the governing damage mechanisms for particular test conditions.

Keywords

creep/fatigue interaction, superalloy, MAR-M 247, high temperature

Citation

Procedia Structural Integrity. 2020, vol. 23, issue 1, p. 197-202.
https://www.sciencedirect.com/science/article/pii/S2452321620301451

Document type

Peer-reviewed

Document version

Published version

Language of document

en

Document licence

Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
http://creativecommons.org/licenses/by-nc-nd/4.0/