Abstract
Precipitation process leading to the formation of long-period stacking ordered (LPSO) structures in dilute MgGdZn and MgYZn alloys during heating at a heating rate of 10 K/min have been examined by in situ synchrotron radiation small- and wide-angle scattering measurements. Samples were solution-treated and quenched prior to the measurements. During heating, two distinct temperature regions were observed for both alloys. The one at the lower temperature, clusters without in-plane order appeared, and then dissolved at higher temperatures. Clusters leading to LPSO structures appeared at a higher temperature above 600 K. Streaky peaks appeared above the temperature, suggesting that very thin layers of LPSO structure with relatively large domain size in the in-plane direction were formed. The average cluster–cluster distance in the segregation layer above 600 K was almost constant until dissolution of LPSO structure at 800 K. The average cluster–cluster distance is larger than the ideally ordered superstructures reported for stoichiometric LPSO alloys.
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Acknowledgements
The present work has been financially supported by grant-in-aid for scientific research from JSPS, grant number 18H05476 and Light Metals Education Foundation. SWAXS measurements have been made under approval of 2016B1279, 2021A1241 at SPring8, and 2017G593 and 2019G685 at Photon Factory, Japan.
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Okuda, H., Yamasaki, M., Kawamura, Y. (2022). In Situ Measurements on Formation and Development of LPSO-like Nanostructures in Dilute MgYZn and MgGdZn Alloys. In: Maier, P., Barela, S., Miller, V.M., Neelameggham, N.R. (eds) Magnesium Technology 2022. The Minerals, Metals & Materials Series. Springer, Cham. https://doi.org/10.1007/978-3-030-92533-8_24
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