Chemical Ordering induced Strengthening in Lightweight Mg Alloys

Yunnuo Duan; Qianfeng Gao; Zijian Zhang; Jiali Zhou; Yuze Li; Zongde Kou; Si Lan; Song Tang

doi:10.3390/nano12193488

Chemical Ordering induced Strengthening in Lightweight Mg Alloys

Nanomaterials (Basel). 2022 Oct 5;12(19):3488. doi: 10.3390/nano12193488.

Authors

Yunnuo Duan¹, Qianfeng Gao¹, Zijian Zhang¹, Jiali Zhou¹, Yuze Li², Zongde Kou¹, Si Lan¹, Song Tang¹

Affiliations

¹ Herbert Gleiter Institute of Nanoscience, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
² School of Physical Science and Technology, Northwestern Polytechnical University, Xi'an 710100, China.

Abstract

The influence of structure and composition on precipitation phenomena in Al-bearing BCC/HCP Mg alloys are studied via diffusion couple technique. Interdiffusion induced by the resultant composition gradient results in a change in crystal structure from HCP to BCC in the diffusion zone. The Vickers hardness in the diffusion zone is much higher than that in the Mg-5.5at.%Al and Mg-38at.%Li, which is attributed to the chemical ordering by nano-sized secondary ordered D0₃-Mg₃Al precipitation in the BCC Mg-Li-Al diffusion zone. The reasons for different precipitation in Al-bearing Mg alloys with various matrices are discussed. Generating ordered precipitates can be an effective approach to improve both strength and ductility in HCP Mg alloys.

Keywords: Mg alloy; diffusion couple; ordered phases; phase transformation; precipitation strengthening.

Abstract

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