| Autor: |
Gerardo Garcés, Judit Medina, Pablo Pérez, Rafael Barea, Hyunkyu Lim, Shae K. Kim, Emad Maawad, Norbert Schell, Paloma Adeva |
| Jazyk: |
angličtina |
| Rok vydání: |
2024 |
| Předmět: |
|
| Zdroj: |
Metals, Vol 14, Iss 5, p 530 (2024) |
| Druh dokumentu: |
article |
| ISSN: |
2075-4701 |
| DOI: |
10.3390/met14050530 |
| Popis: |
A suitable heat treatment in the Mg97Gd2Zn1 (at.%) alloy in the as-cast condition results, after extrusion at high temperature, in a two-phase lamellar microstructure consisting of magnesium grains with thin lamellar shape precipitates and long fibers of the 14H-Long-Period Stacking Ordered (LPSO) phase elongated in the extrusion direction. The magnesium matrix is not fully recrystallized and highly oriented coarse non-dynamically recrystallized (non-DRXed) grains (17% volume fraction) elongated along the extrusion direction remain in the material. The deformation mechanisms of the extruded alloy have been studied measuring the evolution of the internal strains during in situ tension and compression tests using synchrotron diffraction radiation. The data demonstrate that the macroscopic yield stress is governed by the activation of the basal slip system in the randomly oriented equiaxed dynamic recrystallized (DRXed) grains. Non-DRXed grains, due to their strong texture, are favored oriented for the activation of tensile twinning. However, the presence of lamellar-shape precipitates strongly delays the propagation of lenticular thin twins through these highly oriented grains and they have no effect on the onset of the plastic deformation. Therefore, the tension–compression asymmetry is low since the plasticity mechanism is independent of the stress mode. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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