Abstract
Understanding phase stability and precipitation at intermediate temperatures is crucial for tailoring microstructures and mechanical properties of L12-strengthened multicomponent alloys. In this study, the precipitate type, morphology, and distribution of (CoCrNi)100−2x(AlTi)x (x = 3, 5, and 7 at.%) medium-entropy alloys (MEAs) at 600-900 °C were systematically investigated through a combination of scanning electron microscopy, energy dispersive x-ray spectroscopy, x-ray diffraction, electron backscatter diffraction, and thermodynamic calculations. Our results reveal that the Al and Ti additions promote the destabilization of supersaturated fcc into L12 and σ phases, and the dominating phases of the MEAs change from fcc + L12 to fcc + L12 + σ and to L12 + σ + L21 phases as the Al and Ti concentrations increase. In addition, increasing the temperature leads to a change of precipitate morphology from lamellar to granular microstructures. The effects of alloying additions and aging temperature on the phase stability, precipitation behavior, and mechanical properties of the MEAs were discussed from the thermodynamic and kinetic points of view.
Similar content being viewed by others
References
J.W. Yeh, S.K. Chen, S.J. Lin, J.Y. Gan, T.S. Chin, T.T. Shun, C.H. Tsau, and S.Y. Chang, Nanostructured High-Entropy Alloys with Multiple Principal Elements: Novel Alloy Design Concepts and Outcomes, Adv. Eng. Mater., 2004, 6(5), p 299–303.
M.C. Gao, Progress in High-Entropy Alloys, JOM, 2014, 66(10), p 1964–1965.
Y. Zhang, T.T. Zuo, Z. Tang, M.C. Gao, K.A. Dahmen, P.K. Liaw, and Z.P. Lu, Microstructures and Properties of High-Entropy Alloys, Prog. Mater Sci., 2014, 61, p 1–93.
D.B. Miracle, and O.N. Senkov, A Critical Review of High Entropy Alloys and Related Concepts, Acta Mater., 2017, 122, p 448–511.
E.P. George, D. Raabe, and R.O. Ritchie, High-Entropy Alloys, Nat. Rev. Mater., 2019, 4(8), p 515–534.
Q. Lin, J. Liu, X. An, H. Wang, Y. Zhang, and X. Liao, Cryogenic-Deformation-Induced Phase Transformation in an FeCoCrNi High-Entropy Alloy, Mater. Res. Lett., 2018, 6(4), p 236–243.
D. Wei, X. Li, S. Schönecker, J. Jiang, W.-M. Choi, B.-J. Lee, H.S. Kim, A. Chiba, and H. Kato, Development of Strong and Ductile Metastable Face-Centered Cubic Single-Phase High-Entropy Alloys, Acta Mater., 2019, 181, p 318–330.
Y. Ma, J. Hao, J. Jie, Q. Wang, and C. Dong, Coherent Precipitation and Strengthening in a Dual-Phase AlNi2Co2Fe1.5Cr1.5 High-Entropy Alloy, Mater. Sci. Eng. A, 2019, 764, p 138241.
B. Gwalani, D. Choudhuri, V. Soni, Y. Ren, M. Styles, J. Hwang, S. Nam, H. Ryu, S.H. Hong, and R. Banerjee, Cu Assisted Stabilization and Nucleation of L12 Precipitates in Al0.3CuFeCrNi2 fcc-Based High Entropy Alloy, Acta Mater., 2017, 129, p 170–182.
S. Antonov, M. Detrois, and S. Tin, Design of Novel Precipitate-Strengthened Al-Co-Cr-Fe-Nb-Ni High-Entropy Superalloys, Metall. Mater. Trans. A, 2018, 49(1), p 305–320.
Z. Wang, W. Zhou, L. Fu, J. Wang, R. Luo, X. Han, B. Chen, and X. Wang, Effect of Coherent L12 Nanoprecipitates on the Tensile Behavior of a fcc-Based High-Entropy Alloy, Mater. Sci. Eng. A, 2017, 696, p 503–510.
Y.-J. Chang, and A.-C. Yeh, The Formation of Cellular Precipitate and Its Effect on the Tensile Properties of a Precipitation Strengthened High Entropy Alloy, Mater. Chem. Phys., 2018, 210, p 111–119.
Y. Zhao, T. Yang, Y. Tong, J. Wang, J. Luan, Z. Jiao, D. Chen, Y. Yang, A. Hu, and C. Liu, Heterogeneous Precipitation Behavior and Stacking-Fault-Mediated Deformation in a CoCrNi-Based Medium-Entropy Alloy, Acta Mater., 2017, 138, p 72–82.
T.-K. Tsao, A.-C. Yeh, C.-M. Kuo, K. Kakehi, H. Murakami, J.-W. Yeh, and S.-R. Jian, The High Temperature Tensile and Creep Behaviors of High Entropy Superalloy, Sci. Rep., 2017, 7(1), p 12658.
M.-H. Tsai, H. Yuan, G. Cheng, W. Xu, K.-Y. Tsai, C.-W. Tsai, W.W. Jian, C.-C. Juan, W.-J. Shen, and M.-H. Chuang, Morphology, Structure and Composition of Precipitates in Al0.3CoCrCu0.5FeNi High-Entropy Alloy, Intermetallics, 2013, 32, p 329–336.
X. Xu, P. Liu, S. Guo, A. Hirata, T. Fujita, T. Nieh, C. Liu, and M. Chen, Nanoscale Phase Separation in a fcc-Based CoCrCuFeNiAl0.5 High-Entropy Alloy, Acta Mater., 2015, 84, p 145–152.
A.M. Manzoni, S. Singh, H.M. Daoud, R. Popp, R. Völkl, U. Glatzel, and N. Wanderka, On the Path to Optimizing the Al-Co-Cr-Cu-Fe-Ni-Ti High Entropy Alloy Family for High Temperature Applications, Entropy, 2016, 18(4), p 104.
S. Guo, Phase Selection Rules for Cast High Entropy Alloys: An Overview, Mater. Sci. Technol., 2015, 31(10), p 1223–1230.
J. He, H. Wang, H. Huang, X. Xu, M. Chen, Y. Wu, X. Liu, T. Nieh, K. An, and Z. Lu, A Precipitation-Hardened High-Entropy Alloy with Outstanding Tensile Properties, Acta Mater., 2016, 102, p 187–196.
Y. Zhao, H. Chen, Z. Lu, and T. Nieh, Thermal Stability and Coarsening of Coherent Particles in a Precipitation-Hardened (NiCoFeCr)94Ti2Al4 High-Entropy Alloy, Acta Mater., 2018, 147, p 184–194.
Y. Wu, F. Zhang, X. Yuan, H. Huang, X. Wen, Y. Wang, M. Zhang, H. Wu, X. Liu, and H. Wang, Short-Range Ordering and Its Effects on Mechanical Properties of High-Entropy Alloys, J. Mater. Sci. Technol., 2021, 62, p 214–220.
B. Gwalani, V. Soni, D. Choudhuri, M. Lee, J. Hwang, S. Nam, H. Ryu, S.H. Hong, and R. Banerjee, Stability of Ordered L12 and B2 Precipitates in Face Centered Cubic Based High Entropy Alloys-Al0.3CoFeCrNi and Al0.3CuFeCrNi2, Scr. Mater., 2016, 123, p 130–134.
T. Borkar, B. Gwalani, D. Choudhuri, C. Mikler, C. Yannetta, X. Chen, R.V. Ramanujan, M. Styles, M. Gibson, and R. Banerjee, A Combinatorial Assessment of AlxCrCuFeNi2 (0 < c < 1.5) Complex Concentrated Alloys: Microstructure, Microhardness, and Magnetic Properties, Acta Mater., 2016, 116, p 63–76.
C.-W. Lin, M.-H. Tsai, C.-W. Tsai, J.-W. Yeh, and S.-K. Chen, Microstructure and Aging Behaviour of Al5Cr32Fe35Ni22Ti6 High Entropy Alloy, Mater. Sci. Technol., 2015, 31(10), p 1165–1170.
X.H. Du, W.P. Li, H.T. Chang, T. Yang, G.S. Duan, B.L. Wu, J.C. Huang, F.R. Chen, C.T. Liu, W.S. Chuang, Y. Lu, M.L. Sui, and E.W. Huang, Dual Heterogeneous Structures Lead to Ultrahigh Strength and Uniform Ductility in a Co-Cr-Ni Medium-Entropy Alloy, Nat. Commun., 2020, 11(1), p 2390.
Y. Zhao, T. Yang, B. Han, J. Luan, D. Chen, W. Kai, C.T. Liu, and J.-J. Kai, Exceptional Nanostructure Stability and Its Origins in the CoCrNi-Based Precipitation-Strengthened Medium-Entropy Alloy, Mater. Res. Lett., 2019, 7(4), p 152–158.
N. An, Y. Sun, Y. Wu, J. Tian, Z. Li, Q. Li, J. Chen, and X. Hui, High Temperature Strengthening via Nanoscale Precipitation in Wrought CoCrNi-Based Medium-Entropy Alloys, Mater. Sci. Eng. A, 2020, 798, p 140213.
R. Jenkins, Profile Data Acquisition for the JCPDS-ICDD Database, Aust. J. Phys., 1988, 41(2), p 145–154.
L. Fan, T. Yang, J. Luan, and Z. Jiao, Control of Discontinuous and Continuous Precipitation of γ′-Strengthened High-Entropy Alloys Through Nanoscale Nb Segregation cand Partitioning, J. Alloys Compd., 2020, 832, p 154903.
L. Fan, T. Yang, Y. Zhao, J. Luan, G. Zhou, H. Wang, Z. Jiao, and C.-T. Liu, Ultrahigh Strength and Ductility in Newly Developed Materials with Coherent Nanolamellar Architectures, Nat. Commun., 2020, 11(1), p 1–8.
M. Doi, T. Miyazaki, and T. Wakatsuki, The Effect of Elastic Interaction Energy on the Morphology of γ′ Precipitates in Nickel-Based Alloys, Mater. Sci. Eng., 1984, 67(2), p 247–253.
R. Wagner, R. Kampmann, and P.W. Voorhees, Homogeneous Second-Phase Precipitation, Phase Transform. Mater., 2001, 5, p 309.
A. Wilson, Formation and Effect of Topologically Close-Packed Phases in Nickel-Base Superalloys, Mater. Sci. Technol., 2017, 33(9), p 1108–1118.
D. Choudhuri, T. Alam, T. Borkar, B. Gwalani, A. Mantri, S. Srinivasan, M. Gibson, and R. Banerjee, Formation of a Huesler-Like L21 Phase in a CoCrCuFeNiAlTi High-Entropy Alloy, Scr. Mater., 2015, 100, p 36–39.
T. Yang, Y. Zhao, L. Fan, J. Wei, J. Luan, W. Liu, C. Wang, Z. Jiao, J. Kai, and C. Liu, Control of Nanoscale Precipitation and Elimination of Intermediate-Temperature Embrittlement in Multicomponent High-Entropy Alloys, Acta Mater., 2020, 189, p 47–59.
Acknowledgements
This research was supported by the Early Career Scheme from the Research Grants Council of Hong Kong (25202719), State Key Laboratory for Advanced Metals and Materials Open Fund (2021-ZD04), Guangzhou International Science & Technology Cooperation Program (201907010026), and PolyU internal funds (P0009738, P0000538, and P0013994).
Author information
Authors and Affiliations
Corresponding author
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
This article is part of a special topical focus in the Journal of Phase Equilibria and Diffusion on the Thermodynamics and Kinetics of High-Entropy Alloys. This issue was organized by Dr. Michael Gao, National Energy Technology Laboratory; Dr. Ursula Kattner, NIST; Prof. Raymundo Arroyave, Texas A&M University; and the late Dr. John Morral, The Ohio State University.
Supplementary Information
Below is the link to the electronic supplementary material.
Rights and permissions
About this article
Cite this article
Fang, J.Y.C., Liu, W.H., Luan, J.H. et al. Phase Stability and Precipitation in L12-Strengthened CoCrNi Medium-Entropy Alloys at Intermediate Temperatures. J. Phase Equilib. Diffus. 42, 781–793 (2021). https://doi.org/10.1007/s11669-021-00919-4
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11669-021-00919-4