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Pseudo-structural Transition and Thermal Stress-Induced Microcracking in the NdCu Intermetallic

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Abstract

In this paper, the phase transition, thermal expansion, thermal properties, and the internal microcracks of the NdCu phase are studied in detail. The research shows that the NdCu is stabilized by thermal vibrational entropy with a FeB-type crystal structure, the crystallographic symmetry remains the same from room temperature to 973 K, and only the unit cell constants deviate from the law of linear change near 780 K. Such deviation of the lattice constants is different from the traditional viewpoints of structural phase transition. It is not driven by thermodynamics but by the anisotropic expansion of lattice along different crystallographic axes, resulting in anisotropic stress in different directions. The stresses are eventually released in the form of internal microcracks.

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Acknowledgments

This work was supported by the National Natural Science Foundation of China (No. 51861010), the Talent introduction project of the Sichuan University of Science & Engineering (No.2020RC14), and the Open Fund of Material Corrosion and Protection Sichuan Key Laboratory (No.20220CL05).

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Authors and Affiliations

  1. School of Materials Science and Engineering, Sichuan University of Science and Engineering, Zigong, People’s Republic of China

    Wen Zhang & YuQi Yang

  2. Material Corrosion and Protection Key Laboratory of Sichuan Province, Sichuan University of Science and Engineering, Zigong, People’s Republic of China

    Wen Zhang & YuQi Yang

  3. Dongguan Mentech Optical & Magnetic Co., Ltd., Dongguan, People’s Republic of China

    Ping Yan

  4. School of Materials Science and Engineering, Jiangxi University of Science and Engineering, Ganzhou, People’s Republic of China

    YuQi Yang

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  1. Wen Zhang
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Zhang, W., Yan, P. & Yang, Y. Pseudo-structural Transition and Thermal Stress-Induced Microcracking in the NdCu Intermetallic. J. Phase Equilib. Diffus. 44, 17–27 (2023). https://doi.org/10.1007/s11669-022-01020-0

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