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Atomic-scale observation of β′ and LPSO phase in Mg–Y–Ni alloy by HAADF-STEM

Published online by Cambridge University Press:  03 May 2019

Liping Yu ,
Xia Chen ,
Shaohan Wang  and
Bin Chen Open the ORCID record for Bin Chen [Opens in a new window]
Liping Yu
Affiliation:
The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081, China
Xia Chen*
Affiliation:
The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081, China
Shaohan Wang
Affiliation:
Frontier Research Center for Materials Structure, Shanghai Jiao Tong University, Shanghai 200240, China
Bin Chen*
Affiliation:
Frontier Research Center for Materials Structure, Shanghai Jiao Tong University, Shanghai 200240, China
*
a)Address all correspondence to these authors. e-mail: chenxiaocy@wust.edu.cn
b)e-mail: steelboy@sjtu.edu.cn
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Abstract

This paper reports on an atomic-scale investigation into the β′ precipitates and the long-period stacking ordered phase (LPSO) in Mg–5Y–2.5Ni–0.5Zr (at.%) alloy, using Cs-corrected high angle annular dark field-scanning transmission electron microscopy (HAADF-STEM). The results displayed that the 18R-type and 14H-type LPSO phases coexisted in the as-cast and the solid solution states, and the 18R-type and 14H-type LPSO structures were thermal stable. After aging treatment, the aging peak hardness reached 138 HV at 225 °C for 48 h. The significant increase in hardness was attributed to the formation of the metastable β′ phase. The lattice parameters of a and b axes for β′ phases are a = 0.65 nm, b = 2.20 nm, and c = 0.52 nm by HAADF-STEM. The interaction between the LPSO phase and the β′ can be found. The atomic-scale interactions between the LPSO and β′ phases are divided into two parts: under-aging and peak-aging conditions between the building blocks.

Keywords

magnesium alloyaging treatmentprecipitateslong-period stacking ordered (LPSO) phaseHAADF-STEM
Type
Article
Information
Journal of Materials Research , Volume 34 , Issue 20 , 28 October 2019 , pp. 3545 - 3553
Copyright
Copyright © Materials Research Society 2019 

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References

Leng, Z., Zhang, J., Yin, T., Zhang, L., Liu, S., Zhang, M., and Wu, R.: Microstructure and mechanical properties of Mg–9RY–4Cu alloy with long period stacking ordered phase. Mater. Sci. Eng., A 580, 196 (2013).CrossRefGoogle Scholar
Itoi, T., Inazawa, T., Yamasaki, M., Kawamura, Y., and Hirohashi, M.: Microstructure and mechanical properties of Mg–Zn–Y alloy sheet prepared by hot-rolling. Mater. Sci. Eng., A 560, 216 (2013).CrossRefGoogle Scholar
Kim, J.K., Sandlöbes, S., and Raabe, D.: On the room temperature deformation mechanisms of a Mg–Y–Zn alloy with long-period-stacking-ordered structures. Acta Mater. 82, 414 (2015).10.1016/j.actamat.2014.09.036CrossRefGoogle Scholar
Shao, X.H., Yang, Z.Q., and Ma, X.L.: Strengthening and toughening mechanisms in Mg–Zn–Y alloy with a long period stacking ordered structure. Acta Mater. 58, 4760 (2010).CrossRefGoogle Scholar
Hagihara, K., Kinoshita, A., Sugino, Y., Yamasaki, M., Kawamura, Y., Yasuda, H.Y., and Umakoshi, Y.: Effect of long-period stacking ordered phase on mechanical properties of Mg97Zn1Y2 extruded alloy. Acta Mater. 58, 6282 (2010).CrossRefGoogle Scholar
Saal, J.E. and Wolverton, C.: Thermodynamic stability of Mg-based ternary long-period stacking ordered structures. Acta Mater. 68, 325 (2014).CrossRefGoogle Scholar
Egusa, D. and Abe, E.: The structure of long period stacking/order Mg–Zn–RE phases with extended non-stoichiometry ranges. Acta Mater. 60, 166 (2012).CrossRefGoogle Scholar
Qin, D., Wang, J., Chen, Y., Lu, R., and Pan, F.: Effect of long period stacking ordered structure on the damping capacities of Mg–Ni–Y alloys. Mater. Sci. Eng., A 624, 9 (2015).CrossRefGoogle Scholar
Wu, S., Zhang, J., Zhang, Z., Xu, C., Nie, K., and Niu, X.: A high strength and good ductility Mg–Y–NI–TI alloy with long period stacking ordered structure processed by hot rolling and aging treatment. Mater. Sci. Eng., A 648, 134 (2015).CrossRefGoogle Scholar
Zhu, S.M., Lapovok, R., Nie, J.F., Estrin, Y., and Mathaudhu, S.N.: Microstructure and mechanical properties of LPSO phase dominant Mg85.8Y7.1Zn7.1 and Mg85.8Y7.1Ni7.1 alloys. Mater. Sci. Eng., A 692, 35 (2017).CrossRefGoogle Scholar
Itoi, T., Takahashi, K., Moriyama, H., and Hirohashi, M.: A high-strength Mg–Ni–Y alloy sheet with a long-period ordered phase prepared by hot-rolling. Scr. Mater. 59, 1155 (2008).CrossRefGoogle Scholar
Nie, J.F. and Muddle, B.C.: Characterisation of strengthening precipitate phases in a Mg–Y–Nd alloy. Acta Mater. 48, 1691 (2000).CrossRefGoogle Scholar
Liang, S., Guan, D., Tan, X., Chen, L., and Tang, Y.: Effect of isothermal aging on the microstructure and properties of as-cast Mg–Gd–Y–Zr alloy. Mater. Sci. Eng., A 528, 1589 (2011).10.1016/j.msea.2010.10.082CrossRefGoogle Scholar
Apps, P.J., Karimzadeh, H., King, J.F., and Lorimer, G.W.: Precipitation reactions in magnesium-rare earth alloys containing yttrium, gadolinium or dysprosium. Scr. Mater. 48, 1023 (2003).10.1016/S1359-6462(02)00596-1CrossRefGoogle Scholar
Liu, K., Rokhlin, L.L., Elkin, F.M., Tang, D., and Meng, J.: Effect of ageing treatment on the microstructures and mechanical properties of the extruded Mg–7Y–4Gd–1.5Zn–0.4Zr alloy. Mater. Sci. Eng., A 527, 828 (2010).CrossRefGoogle Scholar
Nishijima, M., Hiraga, K., Yamasaki, M., and Kawamura, Y.: Characterization of beta prime phase precipitates in an Mg–5 at.% Gd alloy aged in a peak hardness condition, studied by high-angle annular detector dark-field scanning transmission electron microscopy. Mater. Trans. 47, 2109 (2006).CrossRefGoogle Scholar
Nishijima, M., Yubuta, K., and Hiraga, K.: Characterization of beta prime precipitate phase in Mg–2 at.% Y alloy aged to peak hardness condition by high-angle annular detector dark-field scanning transmission electron microscopy (HAADF-STEM). Mater. Trans. 48, 84 (2007).10.2320/matertrans.48.84CrossRefGoogle Scholar
Jin, Q-Q., Fang, C-F., and Mi, S-B.: Formation of long-period stacking ordered structures in Mg88M5Y7 (M = Ti, Ni and Pb) casting alloys. J. Alloys Compd. 568, 21 (2013).CrossRefGoogle Scholar
Jiang, M., Zhang, S., Bi, Y., Li, H., Ren, Y., and Qin, G.: Phase equilibria of the long-period stacking ordered phase in the Mg–Ni–Y system. Intermetallics 57, 127 (2015).CrossRefGoogle Scholar
Mi, S-B. and Jin, Q-Q.: New polytypes of long-period stacking ordered structures in Mg–Co–Y alloys. Scr. Mater. 68, 635 (2013).CrossRefGoogle Scholar
Nie, J.F., Zhu, Y.M., and Morton, A.J.: On the structure, transformation and deformation of long-period stacking ordered phases in Mg–Y–Zn alloys. Metall. Mater. Trans. A 45, 3338 (2014).CrossRefGoogle Scholar
Zhu, Y.M., Morton, A.J., and Nie, J.F.: The 18R and 14H long-period stacking ordered structures in Mg–Y–Zn alloys. Acta Mater. 58, 2936 (2010).CrossRefGoogle Scholar
Kim, J.K., Ko, W.S., Sandlöbes, S., Heidelmann, M., Grabowski, B., and Raabe, D.: The role of metastable LPSO building block clusters in phase transformations of an Mg–Y–Zn alloy. Acta Mater. 112, 171 (2016).CrossRefGoogle Scholar
Wu, Y.J., Xu, C., Zheng, F.Y., Peng, L.M., Zhang, Y., and Ding, W.J.: Formation and characterization of microstructure of as-cast Mg–6Gd–4Y–xZn–0.5Zr (x = 0.3, 0.5, and 0.7 wt%) alloys. Mater. Charact. 79, 93 (2013).CrossRefGoogle Scholar
Liu, H., Xue, F., Bai, J., and Zhou, J.: Microstructure and mechanical properties of a Mg94Y4Ni2 alloy with long period stacking ordered structure. J. Mater. Eng. Perform. 22, 3500 (2013).10.1007/s11665-013-0617-9CrossRefGoogle Scholar
Liu, H., Xue, F., Bai, J., Zhou, J., and Liu, X.: Effect of substitution of 1 at.% Ni for Zn on the microstructure and mechanical properties of Mg94Y4Zn2 alloy. Mater. Sci. Eng., A 585, 387 (2013).CrossRefGoogle Scholar
Xue, Z., Ren, Y., Luo, W., Zheng, R., and Xu, C.: Effect of aging treatment on the precipitation behavior and mechanical properties of Mg–9Gd–3Y–1.5Zn–0.5Zr alloy. J. Mater. Eng. Perform. 26, 5963 (2017).10.1007/s11665-017-2755-yCrossRefGoogle Scholar
Li, Y.X., Zhu, G.Z., Qiu, D., Yin, D.D., Rong, Y.H., and Zhang, M.X.: The intrinsic effect of long period stacking ordered phases on mechanical properties in Mg–RE based alloys. J. Alloys Compd. 660, 252 (2016).CrossRefGoogle Scholar
Zheng, J. and Chen, B.: Interactions between long-period stacking ordered phase and β′ precipitate in Mg–Gd–Y–Zn–Zr alloy: Atomic-scale insights from HAADF-STEM. Mater. Lett. 176, 223 (2016).CrossRefGoogle Scholar
Zhu, Y.M., Morton, A.J., and Nie, J.F.: Growth and transformation mechanisms of 18R and 14H in Mg–Y–Zn alloys. Acta Mater. 60, 6562 (2012).CrossRefGoogle Scholar