Skip to main content

Phase Stability and Precipitation in L12-Strengthened CoCrNi Medium-Entropy Alloys at Intermediate Temperatures

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.

This is a preview of subscription content, access via your institution.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12

References

  1. 1.

    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.

    Article  Google Scholar 

  2. 2.

    M.C. Gao, Progress in High-Entropy Alloys, JOM, 2014, 66(10), p 1964–1965.

    Article  Google Scholar 

  3. 3.

    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.

    Article  Google Scholar 

  4. 4.

    D.B. Miracle, and O.N. Senkov, A Critical Review of High Entropy Alloys and Related Concepts, Acta Mater., 2017, 122, p 448–511.

    ADS  Article  Google Scholar 

  5. 5.

    E.P. George, D. Raabe, and R.O. Ritchie, High-Entropy Alloys, Nat. Rev. Mater., 2019, 4(8), p 515–534.

    ADS  Article  Google Scholar 

  6. 6.

    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.

    Article  Google Scholar 

  7. 7.

    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.

    ADS  Article  Google Scholar 

  8. 8.

    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.

    Article  Google Scholar 

  9. 9.

    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.

    ADS  Article  Google Scholar 

  10. 10.

    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.

    Article  Google Scholar 

  11. 11.

    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.

    Article  Google Scholar 

  12. 12.

    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.

    Article  Google Scholar 

  13. 13.

    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.

    ADS  Article  Google Scholar 

  14. 14.

    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.

    ADS  Article  Google Scholar 

  15. 15.

    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.

    Article  Google Scholar 

  16. 16.

    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.

    Article  Google Scholar 

  17. 17.

    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.

    ADS  Article  Google Scholar 

  18. 18.

    S. Guo, Phase Selection Rules for Cast High Entropy Alloys: An Overview, Mater. Sci. Technol., 2015, 31(10), p 1223–1230.

    Article  Google Scholar 

  19. 19.

    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.

    ADS  Article  Google Scholar 

  20. 20.

    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.

    ADS  Article  Google Scholar 

  21. 21.

    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.

    Article  Google Scholar 

  22. 22.

    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.

    Article  Google Scholar 

  23. 23.

    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.

    ADS  Article  Google Scholar 

  24. 24.

    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.

    Article  Google Scholar 

  25. 25.

    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.

    ADS  Article  Google Scholar 

  26. 26.

    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.

    Article  Google Scholar 

  27. 27.

    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.

    Article  Google Scholar 

  28. 28.

    R. Jenkins, Profile Data Acquisition for the JCPDS-ICDD Database, Aust. J. Phys., 1988, 41(2), p 145–154.

    ADS  Article  Google Scholar 

  29. 29.

    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.

    Article  Google Scholar 

  30. 30.

    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.

    ADS  Article  Google Scholar 

  31. 31.

    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.

    Article  Google Scholar 

  32. 32.

    R. Wagner, R. Kampmann, and P.W. Voorhees, Homogeneous Second-Phase Precipitation, Phase Transform. Mater., 2001, 5, p 309.

    Google Scholar 

  33. 33.

    A. Wilson, Formation and Effect of Topologically Close-Packed Phases in Nickel-Base Superalloys, Mater. Sci. Technol., 2017, 33(9), p 1108–1118.

    Article  Google Scholar 

  34. 34.

    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.

    Article  Google Scholar 

  35. 35.

    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.

    ADS  Article  Google Scholar 

Download references

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

Affiliations

Authors

Corresponding author

Correspondence to Z. B. Jiao.

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

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

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. (2021). https://doi.org/10.1007/s11669-021-00919-4

Download citation

Keywords

  • medium entropy alloy
  • precipitation
  • phase relation
  • precipitate microstructure