Fe13Ga9 intermetallic in bcc-base Fe–Ga alloy. (April 2021)

• Record Type: Journal Article
• Authors: Leineweber, A.; Becker, H.; Boev, A.; Bobrikov, I.A.; Balagurov, A.M.; Golovin, I.S.
• Is Part Of: Intermetallics. Volume 131(2021)
• Publication Date: 2021-04
• Subjects: Functional alloys (magnetic, electrical, biomedical) -- Phase transformation (crystallographic aspects kinetics and mechanisms) -- Thermodynamic properties -- Microstructure -- ab–initio calculations -- X-ray and neutron diffraction; Intermetallic compounds -- Metallography -- Periodicals; Metallic glasses -- Periodicals; Composés intermétalliques -- Métallographie -- Périodiques; 669.94
• DOI: 10.1016/j.intermet.2020.107059
• Languages: English
• ISSNs: 0966-9795

Abstract

Abstract: Fe−Ga alloys (Galfenols) are of interest due to their pronounced magnetostriction, whereby the mechanistic understanding is limited. By means of powder X-ray and neutron diffraction it is shown that as-cast Fe-38.4 at%Ga alloy consists of Fe13 Ga9 intermetallic with a monoclinic Ni2 In/NiAs-related structure, which coexists with bcc solid solution. By means of electron backscatter diffraction it is shown that the Fe13 Ga9 intermetallic develops with two different but closely related orientation relationships with respect to the matrix, which can be derived by the relation between the atomic structures of Fe13 Ga9 and the matrix. First principles calculations reveal that Fe13 Ga9 should be stable at 0 K and that this phase may also expected to develop in alloys for lower Ga contents and may have to be considered upon interpreting macroscopically observed magnetostriction. Highlights: Fe13 Ga9 intermetallic develops in as-cast Fe-38at.%Ga alloy. Crystal structure was refined based on powder X-ray and neutron diffraction data. DFT calculations imply that Fe13 Ga9 is stable at 0 K against other Fe–Ga phases. Crystal structure can be related with crystal structure of bcc matrix. Role of this phase in view of magnetostriction in Galfenols is to be eludicated.