|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Magnesium Technology 2017
||Zn Segregation at Precipitate/Matrix Interface in Mg-Sn-Zn Alloys
||Chaoqiang Liu, Houwen Chen, Jian-Feng Nie
|On-Site Speaker (Planned)
Magnesium-tin based alloys have received considerable attention in the past 15 years for developing high strength alloys. Mg-Sn binary alloys are precipitation hardenable, but their age-hardening response is moderate. Additions of Zn can significantly improve the age-hardening response of binary Mg-Sn alloys by refining the distribution of Mg2Sn precipitates. To understand the role of Zn in the precipitation process, the Mg2Sn precipitates with different morphologies and orientations in under-, peak- and over-aged samples of a Mg-9.8Sn-1.2Zn (wt.%) alloy are characterized by high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and STEM X-ray mapping. It is found that Zn atoms invariably segregate to the Mg2Sn-Mg interface, irrespective of the interfacial structures and orientation relationships of the Mg2Sn precipitates. This finding provides an insight to the understanding of the enhanced nucleation of Mg2Sn precipitates in Mg-Sn-Zn alloys.