Low-Cycle-Fatigue Performance of Stress-Aged EN AW-7075 Alloy

Sajadifar, Seyed Vahid; Krooß, Philipp; Krochmal, Marcel; Wegener, Thomas; Heidarzadeh, Akbar; Fröck, Hannes; Zavašnik, Janez; Kessler, Olaf; Niendorf, Thomas

doi:10.1002/adem.202300090

Item

ITEM ACTIONSEXPORT

Add to Basket

Local TagsRelease HistoryDetailsSummary

Released

Journal Article

Low-Cycle-Fatigue Performance of Stress-Aged EN AW-7075 Alloy

MPS-Authors

/persons/resource/persons223021

Zavašnik, Janez
Nano-/ Micromechanics of Materials, Structure and Nano-/ Micromechanics of Materials, Max-Planck-Institut für Eisenforschung GmbH, Max Planck Society;
Centre for Electron Microscopy and Microanalysis, Jožef Stefan Institute, Jamova cesta 39, Ljubljana, Slovenia;

External Resource

No external resources are shared

Fulltext (restricted access)

There are currently no full texts shared for your IP range.

Fulltext (public)

Adv Eng Mater - 2023 - Sajadifar - Low‐Cycle‐Fatigue Performance of Stress‐Aged EN AW‐7075 Alloy.pdf
(Publisher version), 10MB

Supplementary Material (public)

There is no public supplementary material available

Citation

Sajadifar, S. V., Krooß, P., Krochmal, M., Wegener, T., Heidarzadeh, A., Fröck, H., et al. (2023). Low-Cycle-Fatigue Performance of Stress-Aged EN AW-7075 Alloy. Advanced Engineering Materials, 25(15): 2300090. doi:10.1002/adem.202300090.

Cite as: https://hdl.handle.net/21.11116/0000-0010-0B99-6

Abstract

The effect of a novel heat treatment, that is, aging under superimposed external stress, on the fatigue performance and microstructural evolution of a high-strength aluminum alloy (EN AW-7075) is presented. Stress aging, a combination of heat treatment and superimposed external stress, can enhance the mechanical properties of EN AW-7075 under monotonic loading due to the acceleration of precipitation kinetics. Scanning electron microscopy (SEM) and scanning transmission electron microscopy (STEM) reveal that a longer aging time and the presence of superimposed stress both promote the formation and growth of precipitates, that is, the precipitation of strengthening ?? precipitates. This is confirmed by differential scanning calorimetry (DSC) heating experiments of stressless and stress-aged states. Furthermore, stress aging leads to a reduction of dimensions of precipitate-free zones near grain boundaries. Cyclic deformation responses (CDRs) and half-life hysteresis loops are evaluated focusing on the low-cycle fatigue (LCF) performance of different conditions. A noticeable cyclic hardening seen in case of the specimens aged for a short time indicates the occurrence of dynamic strain aging (DSA). Eventually, stress aging allows for an enhancement of the monotonic mechanical properties of EN AW-7075 without degrading the cyclic performance in the LCF regime.