The Effect of Ni on Phase Stability of CoFe Alloy

作者: 戚梦琳 , 倪晓东 :北京科技大学数理学院;

关键词: 第一性原理有序无序转变中间相原子择优占位The First Principle Order-Disorder Transition Mesophase Atomic Site Preference

本工作利用第一性原理的热力学计算方法,研究了等摩尔配比的CoFe和CoFeNi合金的有序无序转变。计算结果的朗道理论分析表明:1) CoFe和CoFeNi合金的基态均为B2相结构;2) CoFe合金的高温平衡相为BCC结构,当达到转变温度时,CoFe合金会发生B2到BCC结构的相转变,有序无序转变温度大致在1400 K,摩尔组态熵变为;3) 随着Ni的添加,合金体系的转变温度会降低,CoFeNi合金发生了非平衡转变,其高温平衡相为FCC结构,有序无序转变温度低于750 K,摩尔组态熵变为。计算结果与两种合金的有序无序转变实验结果相吻合。

Abstract: In this work, the order-disorder transition of CoFe and CoFeNi alloys with equimolar proportions are studied by using the first-principle thermodynamic calculation method. The calculated results of Landau’s theoretical analysis show that: 1) the ground states of CoFe and CoFeNi alloys are B2 phase structure; 2) the high temperature equilibrium phase of CoFe alloy is BCC, when it rises to transition temperature, the phase transition from B2 to BCC will occur in CoFe alloy, the or-der-disorder transition temperature is about 1400 K, and the molar configuration entropy is ; 3) And with the addition of Ni, the transition temperature of the alloy system will decrease, a non-equilibrium transformation occurs in CoFeNi alloy, the high temperature equilibrium phase of CoFeNi alloy is FCC, the order-disorder transition temperature is lower than 750 K, and the mo-lar configuration entropy is . The calculated results are in good agreement with the expe-rimental results of the order-disorder transition of the two alloys.

文章引用: 戚梦琳 , 倪晓东 (2017) Ni对CoFe合金相稳定性的影响。 凝聚态物理学进展, 6, 33-42. doi: 10.12677/CMP.2017.62005


[1] [1] Kogachi, M., Tadachi, N., Kohata, H. and Ishibashi, H. (2005) Magnetism and Point Defect in B2-Type Cofe Alloys. In-termetallics, 13, 535-542.

[2] Gloskovskii, A., Stryganyuk, G., Ouardi, S., Fecher, G.H., Felser, C., Hamrle, J., et al. (2012) Structure Determination of Thin Cofe Films by Anomalous X-Ray Diffraction. Journal of Applied Physics, 112, Article ID: 074903.

[3] Ishibashi, H., Harada, K., Kogachi, M. and Noguchi, S. (2004) Magnetic Properties and Long Range Order Parameter in B2-Type Cofe Alloys. Journal of Magnetism and Magnetic Materials, 272, 774-775.

[4] Chen, Y.T., Jen, S.U., Yao, Y.D., Wu, J.M., Hwang, G.H., Tsai, T.L., et al. (2006) Magnetic, Structural and Electrical Properties of Ordered and Disordered CO50FE50 Films. Jour-nal of Magnetism and Magnetic Materials, 304, 71-74.

[5] Rahaman, M., Ruban, A.V., Mookerjee, A. and Johansson, B. (2011) Magnetic State Effect upon the Order-Disorder Phase Transition in Fe-Co Alloys: A First-Principles Study. Physical Review B, 83, Article ID: 054202.

[6] Montano, P.A. and Seehra, M.S. (1977) Mössbauer Study of the Order-Disorder Andα-Γ Transitions in Fe-Co. Physical Review B, 15, 2437-2441.

[7] Syed, G.S. and Ravi, K.R. (2016) Phase-Evolution in High Entropy Alloys: Role of Synthesis Route. Intermetallics, 73, 40-42.

[8] Singh, A.K. and Subramaniam, A. (2014) On the Formation of Dis-ordered Solid Solutions in Multi-Component Alloys. Journal of Alloys and Compounds, 587, 113-119.

[9] Yeh, J.W. (2013) Alloy Design Strategies and Future Trends in High-Entropy Alloys. Journal of the Minerals, Metals, and Materials Society, 65, 1759-1771.

[10] Yeh, J.W., Chen, S.K., Lin, S.J., Gan, J.Y., Chin, T.S., Shun, T.T., et al. (2004) Nanostructured High-Entropy Alloys with Multiple Principal Elements: Novel Alloy Design Concepts and Outcomes. Advanced Engineering Materials, 6, 299-303.

[11] Ni, X., Chen, N., Shen, J. and Yuan, Y. (2009) Generalized Model for Atomic Site Preference in Crystal and Its Application in Rare-Earth Alloys. Intermetallics, 17, 1-5.

[12] Vitos, L. (2001) Total-Energy Method Based on the Exact Muffin-Tin Orbitals Theory. Physical Review B, 64, Article ID: 014107.

[13] Vitos, L. (2007) Computational Quantum Mechanics for Materi-als Engineers: The Method and Applications. Springer, Berlin.

[14] Vitos, L., Abrikosov, I.A. and Johansson, B. (2001) Anisotropic Lattice Distortions in Random Alloys from First-Principles Theory. Physical Review Letter, 87, Article ID: 156401.

[15] Khan, S.N., Staunton, J.B. and Stocks, G.M. (2016) Statistical Physics of Multicomponent Alloys Using Kkr-Cpa. Physical Review B, 93, Article ID: 054206.

[16] Gyorffy, B.L. (1972) Coherent-Potential Approximation for a Nonoverlapping-Muffin-Tin-Potential Model of Random Substitutional Alloys. Physical Review B, 5, 2382-2384.

[17] Jain, A., Shin, Y. and Persson, K.A. (2016) Computational Predic-tions of Energy Materials Using Density Functional Theory. Nature Reviews Materials, 1, Article ID: 15004.

[18] Vitos, L., Kollár, J. and Skriver, H.L. (1994) Full Charge-Density Calculation of the Surface Energy of Metals. Physical Review B, 49, 16694-16701.

[19] Perdew, J.P., Burke, K. and Ernzerhof, M. (1996) Generalized Gradi-ent Approximation Made Simple. Physical Review Letter, 77, 3865-3868.

[20] Kohn, W. and Sham, L.J. (1965) Self-Consistent Equations Including Exchange and Correlation Effects. Physical Review B, 140, 1133-1138.

[21] Sun, X., Ni, X., Shen, J. and Chen, N. (2011) Effect of Co Additions on B2 Phase Stability of Ni-Poor Niti-Based Alloys. Journal of Alloys and Compounds, 509, 8323-8326.

[22] 冯端, 等. 金属物理学: 相变[M]. 北京: 科学出版社, 1990: 44-47.

[23] 冯端, 金国钧. 凝聚态物理学(上卷)[M]. 北京: 高等教育出版社, 2003: 474-476.

[24] 伍胜健. 数学分析: 第3册[M]. 北京: 北京大学出版社, 2010: 95-100.

[25] 徐祖耀. 材料热力学[M]. 北京: 科学出版社, 2000: 224-228.