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Year 2026
 
Vol 67, Issue 3, [06 - 2026]

Enhancement of magnetic properties of AlNiCuCo35Ti5Nb alloy by magnetic heat treatment technology

DOI:10.46326/JMES.2026.67(3).06

  • Affiliations:

    1 Institute of Technology, General Department of National Defence Industry, Hanoi, Vietnam
    2 Faculty of Electro-Mechanics, Hanoi University of Mining and Geology, Hanoi, Vietnam

  • *Corresponding:
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  • Received: 25th-Dec-2025
  • Revised: 1st-Apr-2026
  • Accepted: 20th-Apr-2026
  • Online: 1st-June-2026
Pages: 66 - 77
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Abstract:

Hard magnetic materials of the Al-Ni-Co system represent an important class of functional materials, widely applied in various engineering and technological fields. Among them, the AlNiCuCo35Ti5Nb alloy is distinguished by the combination of stable magnetic properties such as high coercivity (Hc), large remanence (Br), and superior maximum energy product (BH)max. These features make the alloy highly promising for the fabrication of energy storage components and devices. used in precision electronic devices, as well as in energy technology, mechanical engineering, aerospace, and defense industries. This study investigates the influence of different regimes of magnetic-field-assisted heat treatment on the magnetic characteristics of the AlNiCuCo35Ti5Nb hard magnetic alloy. The alloy samples were produced for the first time domestically using a directional solidification casting method. The results demonstrate that multistage magnetic heat treatment with slow cooling (8.3 0C/min), combined with an isothermal holding stage (800 0C, 15 min), significantly enhances the magnetic properties. Under these conditions, the maximum energy product (BH)max reaches 72.4 kJ/m³, equivalent to the quality of materials from Russia according to GOST 17809-72. This is a consequence of the uniform alignment of the α₁-phase crystals along the direction of the external magnetic field, which enhances the degree of collinearity of the magnetic moments and simultaneously optimizes their morphology.

How to Cite
Tran, T.Manh, Nguyen, H., Nguyen, M.Van, Pham, T.Thi and Nguyen, T.Anh 2026. Enhancement of magnetic properties of AlNiCuCo35Ti5Nb alloy by magnetic heat treatment technology (in Vietnamese). Journal of Mining and Earth Sciences. 67, 3 (Jun, 2026), 66-77. DOI:https://doi.org/10.46326/JMES.2026.67(3).06.
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