Origins of high strength and ductility combination in a Guinier-Preston zone containing Mg-Al-Ca-Mn alloy

SCRIPTA MATERIALIA

卷:163

Article

Bhattacharyya, J. J.¹  Nakata, T.²  Kamado, S.²  Agnew, S. R.¹ 

[1] Univ Virginia, Charlottesville, VA 22904 USA

[2] Nagaoka Univ Technol, Nagaoka, Niigata, Japan

关键词: Rate sensitivity;    Plastic instability;    Haasen plot;    Thermal activation;    Instability analysis;   

DOI  :  10.1016/j.scriptamat.2019.01.013

来源: Elsevier

【 摘 要 】

The excellent strength and ductility combination of a microalloyed Mg-Al-Ca-Mn, in the peak-aged condition, has been reported previously. However, a mechanistic explanation has not been reported. The present work shows that an enhanced strain-rate sensitivity is responsible for this behavior. Increased post-uniform elongation compensates for the decrease in uniform elongation upon aging, resulting in a total elongation comparable to the solutionized material. The thermally activated nature of dislocation interactions with Guinier-Preston (GP) zones are discussed, and the potential for optimizing mechanical properties by engineering the strain-rate sensitivity through microstructural modifications is highlighted. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

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