Skip to main content

An investigation of the thermal stability of an Mg-Dy alloy after processing by high-pressure torsion.

Hanna, A., Azzeddine, H., Huang, Y., Bradai, D., Cabrera, J.M. and Langdon, T.G., 2019. An investigation of the thermal stability of an Mg-Dy alloy after processing by high-pressure torsion. Materials characterization, 151 (May), 519-529.

Full text available as:

[img]
Preview
PDF
Hiba-MaterCharact 2019-accepted manuscript.pdf - Accepted Version
Available under License Creative Commons Attribution Non-commercial No Derivatives.

2MB

DOI: 10.1016/j.matchar.2019.03.040

Abstract

An Mg-0.41Dy (wt%) alloy was successfully processed by high-pressure tension (HPT) through 5 turns at room temperature. The evolution of the recrystallization microstructure and the texture and mechanical properties of the deformed alloy were investigated after annealing at 200 and 400 °C for 1 h using Electron Backscatter Diffraction (EBSD) and Vickers measurements. The recrystallization temperature and activation energy were evaluated using Differential Scanning Calorimetry (DSC). Processing by HPT led to significant grain refinement with an average grain size of ~0.5 ± 0.1 μm which increased to ~1.2 ± 0.8 μm after annealing at 400 °C. This slow increase in grain size at a high temperature demonstrates a good thermal stability of the microstructure. The alloy exhibited two main fiber textures after HPT processing: firstly a typical basal fiber (φ1 = 0–360°, Φ = 0° and φ2 = 0–60°) and secondly a fiber localized at φ1 = 180°, Φ = 60° and φ2 = 0–90°. These textures were retained after annealing at 400 °C. There was no change in the microhardness value after annealing at 200 °C (41 ± 1 Hv) and only a minor decrease after annealing at 400 °C (38.4 ± 0.5 Hv). The DSC results showed that the temperature associated with the recrystallization process increased with increasing heating rate and the activation energy for recrystallization was measured as ~25 kJ mol−1.

Item Type:Article
ISSN:1044-5803
Uncontrolled Keywords:DSC; HPT; Mg-Dy alloy; microstructure; recrystallization; texture
Group:Faculty of Science & Technology
ID Code:32113
Deposited By: Unnamed user with email symplectic@symplectic
Deposited On:29 Mar 2019 14:04
Last Modified:29 Mar 2020 01:08

Downloads

Downloads per month over past year

More statistics for this item...
Repository Staff Only -