|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Characterization of Minerals, Metals, and Materials
||LL-70: In Situ Transmission Electron Microscopy Studies on Solid-state Formation of Quasicrystals in a Mg Alloy
||Zhiqing Yang, Jianfang Liu, Hengqiang Ye
|On-Site Speaker (Planned)
Mg alloys containing icosahedral quasicrystals have excellent mechanical properties. The good metallurgical bonding at the interfaces between quasicrystals and Mg plays an important role in the excellent mechanical properties of this kind of alloys. However, there are deleterious crystalline phases (such as H-Zn3MgY and W-Zn3Mg3Y2) compete strongly with quasicrystals in Mg-Zn-RE (RE, rare-earth elements) alloys. We have studied phase transformations in a Mg-4.2Zn-0.7Y (wt.%) alloy using in situ heating transmission electron microscopy techniques. Small icosahedral quasicrystal particles were formed at H/Mg and W/Mg interfaces through solid-state phase transformations during in situ heating, modifying the interfaces. Importantly, the annealing temperatures are much below the alloys eutectic and peritectic temperatures. Our study provides insights for the development of heat treatment techniques to improve the alloy’s mechanical properties, through interfacial modification at relatively low temperatures. The transformation mechanisms were discussed based on atomic-resolution characterization of quasicrystal/H and quasicrystal/W interfaces.
||Planned: A print-only volume