Phase transformations of HfNbTaTiZr high-entropy alloy at intermediate temperatures

SCRIPTA MATERIALIA

卷:158

Article

Chen, S. Y.¹  Tong, Y.¹  Tseng, K-K²  Yeh, J-W²  Poplawsky, J. D.³  Wen, J. G.⁴  Gao, M. C.^5,6  Kim, G.⁷  Chen, W.⁷  Ren, Y.⁸  Feng, R.¹  Li, W. D.¹  Liaw, P. K.¹ 

[1] Univ Tennessee, Dept Mat Sci & Engn, Knoxville, TN 37996 USA

[2] Natl Tsing Hua Univ, Dept Mat Sci & Engn, High Entropy Mat Ctr, Hsinchu 30013, Taiwan

[3] Oak Ridge Natl Lab, Ctr Nanophases Mat Sci, Oak Ridge, TN 37831 USA

[4] Argonne Natl Lab, Ctr Nanoscale Mat, Argonne, IL 60439 USA

[5] Natl Energy Technol Lab, Albany, OR 97321 USA

[6] AECOM, POB 618, South Park, PA 15129 USA

[7] IIT, Dept Mech Mat & Aerosp Engn, Chicago, IL 60616 USA

[8] Argonne Natl Lab, Xray Sci Div, Argonne, IL 60439 USA

关键词: High-entropy alloys;    Phase decomposition;    Annealing;   

DOI  :  10.1016/j.scriptamat.2018.08.032

来源: Elsevier

【 摘 要 】

The strong and ductile single-phase body-centered-cubic (BCC) HfNbTaTiZr refractory high-entropy alloy (RHEA) is a potential structural material for high-temperature applications. However, the BCC phase stability in the intermediate temperature range (500-900 degrees C) needs to be better understood to make this alloy applicable to industry. In the present work, the phase decomposition of the HfNbTaTiZr RHEA is examined at different temperatures (500-1000 degrees C). Additionally, the formation of BCC Ta-Nb-rich and hexagonal-close-packed (HCP) Hf-Zr-rich precipitates are studied as a function of annealing time at 700 degrees C using a combination of atom probe tomography, transmission electron microscopy, and X-ray diffraction. We found that these BCC and HCP precipitates have preferred orientations with the BCC matrix. (C) 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

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