Finding a New B1-Type Phase in Single Crystals of Fe–Al and Fe–Ga Soft Magnetic Alloys
- 8 Downloads
The atomic structure of Fe–Al (7 and 9 at % Al) and Fe–Ga (18 at % Ga) alloys is studied by X‑ray diffraction using a laboratory four-circle diffractometer. After refining annealing, single-crystal alloy samples were annealed in the ferromagnetic state (T < TC). One sample of the Fe–18 at % Ga alloy, after short holding in the paramagnetic state (T > TC), was quenched in room temperature water. Earlier, the authors reported on the peculiarities of the ordering of alloying atoms in B2 and D03 phase structures in quenched and annealed samples of these alloys. Here, we present and discuss the results of our observations in these alloys of a new phase with a face-centered cubic (fcc) lattice (B1-type structure with NaCl prototype and unit cell parameter ~5.2 nm). The fcc phase appears in the Fe–Al alloy as the aluminum concentration increases from 7 to 9 at %; it is observed in the Fe–18 at % Ga alloy, and its volume fraction increases after annealing in the ferromagnetic state in comparison with a quenched alloy sample. In these alloys (9 at % Al) and (18 at % Ga), different ways of embedding fcc crystals in the bcc phase of single crystals are realized; i.e., the axes of the fcc lattice are directed in four different ways relative to the axes of the bcc lattice.
Keywords:soft magnetic materials iron–aluminum and iron–gallium alloys X-ray diffraction atomic structure new B1-type phase heat treatment
This work was carried out as part of the state task “Magnet” no. AAAA-A18-118020290129-5 and project no. 8-10-2-5 of the Program of the Ural Branch of the Russian Academy of Sciences and was supported by the Russian Foundation for Basic Research (grant no. 18-02-00391).
CONFLICT OF INTEREST
The authors declare that they have no conflicts of interest.
- 1.A. S. Freitas, D. F. de Albuquerque, I. P. Fittipaldi, and N. O. Moreno, J. Magn. Magn. Mater. 362, 226 (2014). https://doi.org/10.1016/j.JMMM2014.03.055Google Scholar
- 3.U. R. Kattner and B. P. Burton, in Desk Handbook: Phase Diagrams for Binary Alloys, 2nd ed., Ed. by H. Oka-moto (ASM Int., Materials Park, OH, 1993), p. 12. http://www.asminternational.org/documents/10192/1850140/57751G_Frontmatter.pdf/c36eeb4ed6ec-4804-b319-e5b0600ea65d.Google Scholar
- 5.Yu. P. Chernenkov, N. V. Ershov, V. A. Lukshina, V. I. Fedorov, and B. K. Sokolov, Phys. B (Amsterdam, Neth.) 396, 220 (2007). https://doi.org/10.1016/j.physb.2007.04.008
- 12.Yu. P. Chernenkov, V. I. Fedorov, V. A. Lukshina, B. K. Sokolov, and N. V. Ershov, Phys. Met. Metallogr. 100, 235 (2005).Google Scholar
- 13.International Tables for Crystallography, Vol. A: Space-Group Symmetry, Ed. by T. Hahn, 5th ed. (Springer, Dordrecht, The Netherlands, 2005), p. 911. http://chembaby.com/wp-content/uploads/2019/02/Hann-Theo-International-Tables-For-Crystallography.-Volume-A.-Space-group-Symmetry.pdf.Google Scholar
- 14.O. Kubaschewski, Phase Diagrams of Binary Fe-based Systems (Springer, Stahleisen, Berlin, Heidelberg, Düsseldorf, 1982), p. 135. https://www.springer.com/gp/book/9783662080269.Google Scholar
- 15.G. Bertotti and F. Fiorillo, in Magnetic Alloys for Technical Applications. Soft Magnetic Alloys, Invar and Elinvar Alloys, Ed. by H. P. J. Wijn (Springer, Berlin, 1994), p. 35. https://link.springer.com/chapter/10.1007/1006502817.Google Scholar
- 17.B. E. Warren, X-Ray Diffraction (Dover, New York, 1990). https://www.amazon.com/s?k=0486663175&ref=nb_sb_noss.Google Scholar