| About this Abstract |
| Meeting |
2023 TMS Annual Meeting & Exhibition
|
| Symposium
|
Magnesium Technology 2023
|
| Presentation Title |
Precipitation Behavior in Low-alloyed Mg-Ca-Zn Alloys |
| Author(s) |
Zehao Li, Taisuke Sasaki, Du Cheng, Kang Wang, Bi-cheng Zhou, Akira Uedono, Tadakatsu Ohkubo, Kazuhiro Hono |
| On-Site Speaker (Planned) |
Zehao Li |
| Abstract Scope |
Low-alloyed Mg-Ca-Zn alloys are promising as a base system of heat-treatable alloys because of their rapid age-hardenability. The trace addition of Zn plays a critical role in accelerating the age-hardening response and following precipitation behavior. This presentation reports on the origin of the rapid age-hardenability and precipitation sequence in a Mg-0.3Ca-0.6Zn (at.%) alloy. Positron annihilation lifetime spectroscopy indicates the absence of excess quenched-in open spaces in the as-quenched condition. Atom probe tomography (APT) results indicated the formation of a large number of Ca-Zn co-clusters in the early stage of aging is responsible for the rapid age-hardening. Microstructure analysis using aberration-corrected scanning transmission electron microscope (STEM) provided further insights into the precipitation sequence. A precise precipitation sequence is established as: S.S.S.S → G.P. zones → η'' → η' → η1 → η. The atomic structures and stability of the precipitates was verified by density functional theory calculations. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Magnesium, Phase Transformations, Characterization |