The Samson phase, β-Mg2Al3, revisited

Michael Feuerbacher; Carsten Thomas; Julien P.A. Makongo; Stefan Hoffmann; Wilder Carrillo-Cabrera; Raul Cardoso; Yuri Grin; Guido Kreiner; Jean Marc Joubert; Thomas Schenk; Joseph Gastaldi; Henri Nguyen-Thi; Nathalie Mangelinck-Nöel; Bernard Billia; Patricia Donnadieu; Aleksandra Czyrska-Filemonowicz; Anna Zielinska-Lipiec; Beata Dubiel; Thomas Weber; Philippe Schaub; Günter Krauss; Volker Gramlich; Jeppe Christensen; Sven Lidin; Daniel Fredrickson; Marek Mihalkovic; Wieslawa Sikora; Janusz Malinowski; Stefan Brühne; Thomas Proffen; Wolf Assmus; Marc De Boissieu; Francoise Bley; Jean Louis Chemin; Jürgen Schreuer; Walter Steurer

doi:10.1524/zkri.2007.222.6.259

The Samson phase, β-Mg₂Al₃, revisited

Michael Feuerbacher, Carsten Thomas, Julien P.A. Makongo, Stefan Hoffmann, Wilder Carrillo-Cabrera, Raul Cardoso, Yuri Grin, Guido Kreiner, Jean Marc Joubert, Thomas Schenk, Joseph Gastaldi, Henri Nguyen-Thi, Nathalie Mangelinck-Nöel, Bernard Billia, Patricia Donnadieu, Aleksandra Czyrska-Filemonowicz, Anna Zielinska-Lipiec, Beata Dubiel, Thomas Weber, Philippe SchaubGünter Krauss, Volker Gramlich, Jeppe Christensen, Sven Lidin, Daniel Fredrickson, Marek Mihalkovic, Wieslawa Sikora, Janusz Malinowski, Stefan Brühne, Thomas Proffen, Wolf Assmus, Marc De Boissieu, Francoise Bley, Jean Louis Chemin, Jürgen Schreuer, Walter Steurer

Research output: Contribution to journal › Review article › peer-review

127 Scopus citations

Abstract

The Al-Mg phase diagram has been reinvestigated in the vicinity of the stability range of the Samson phase, β-Mg₂Al₃ (cF1168). For the composition Mg_38.5Al_61.5, this cubic phase, space group Fd3̄m (no 227), a = 28.242(1) Å, V = 22526(2) Å³, undergoes at 214°C a first-order phase transition to rhombohedral β′-Mg₂Al₃, (hR293), a = 19.968(1) Å, c = 48.9114(8) Å, V = 16889(2) Å³, (i.e. 22519 Å³ for the equivalent cubic unit cell) space group R3m (no 160), a subgroup of index four of Fd3̄m. The structure of the β-phase has been redetermined at ambient temperature as well as in situ at 400°C. It essentially agrees with Samson's model, even in most of the many partially occupied and split positions. The structure of β′-Mg ₂Al₃ is closely related to that of the β-phase. Its atomic sites can be derived from those of the β-phase by group-theoretical considerations. The main difference between the two structures is that all atomic sites are fully occupied in case of the β′-phase. The reciprocal space, Bragg as well as diffuse scattering, has been explored as function of temperature and the β- to β′-phase transition was studied in detail. The microstructures of both phases have been analyzed by electron microscopy and X-ray topography showing them highly defective. Finally, the thermal expansion coefficients and elastic parameters have been determined. Their values are somewhere in between those of Al and Mg.

Original language	English
Pages (from-to)	259-288
Number of pages	30
Journal	Zeitschrift fur Kristallographie
Volume	222
Issue number	6
DOIs	https://doi.org/10.1524/zkri.2007.222.6.259
State	Published - 2007
Externally published	Yes

Funding

took place in the European Network of Excellence on Complex Metallic Alloys, financially supported by the EC under contract n· NMP3-CT-2005-500140. Part of this work has benefited from the use of NPDF at the Lujan Center at Los Alamos Neutron Science Center, funded by DOE Office of Basic Energy Sciences and Los Alamos National Laboratory funded by Department of Energy under contract W-7405-ENG-36. The upgrade of NPDF has been funded by NSF through grant DMR 00-76488. We acknowledge the European Synchrotron Radiation Facility (ESRF) for provision of synchrotron radiation facilities and we would like to thank Michela Brunelli for assistance in using beamline ID31 and supporting experiment HS-2968. We also want to thank the staff of the Swiss/Norwegian Beamline (SNBL) for its support. Valuable contribution of Prof. Phi-lippe A. Buffat (EPFL) to phase identification by electron diffraction and JEMS is kindly acknowledged. One of us (DF) thanks the National Science Foundation for financial support through a postdoctoral research fellowship (grant DMR-0502582).

Funders	Funder number
DOE Office of Basic Energy Sciences and Los Alamos National Laboratory
National Science Foundation	DMR 00-76488, DMR-0502582
U.S. Department of Energy	W-7405-ENG-36
European Commission	NMP3-CT-2005-500140

Keywords

CMA
Elastic parameters
Electron microscopy
Magnesium aluminides
Microstructure
Powder diffraction structure analysis
Samson phase
X-ray diffraction

Access to Document

10.1524/zkri.2007.222.6.259

Cite this

Feuerbacher, M., Thomas, C., Makongo, J. P. A., Hoffmann, S., Carrillo-Cabrera, W., Cardoso, R., Grin, Y., Kreiner, G., Joubert, J. M., Schenk, T., Gastaldi, J., Nguyen-Thi, H., Mangelinck-Nöel, N., Billia, B., Donnadieu, P., Czyrska-Filemonowicz, A., Zielinska-Lipiec, A., Dubiel, B., Weber, T., ... Steurer, W. (2007). The Samson phase, β-Mg₂Al₃, revisited. Zeitschrift fur Kristallographie, 222(6), 259-288. https://doi.org/10.1524/zkri.2007.222.6.259

@article{e9701f43bb814b8f9d2b8414bf1da82d,

title = "The Samson phase, β-Mg2Al3, revisited",

abstract = "The Al-Mg phase diagram has been reinvestigated in the vicinity of the stability range of the Samson phase, β-Mg2Al3 (cF1168). For the composition Mg38.5Al61.5, this cubic phase, space group Fd{\=3}m (no 227), a = 28.242(1) {\AA}, V = 22526(2) {\AA}3, undergoes at 214°C a first-order phase transition to rhombohedral β′-Mg2Al3, (hR293), a = 19.968(1) {\AA}, c = 48.9114(8) {\AA}, V = 16889(2) {\AA}3, (i.e. 22519 {\AA}3 for the equivalent cubic unit cell) space group R3m (no 160), a subgroup of index four of Fd{\=3}m. The structure of the β-phase has been redetermined at ambient temperature as well as in situ at 400°C. It essentially agrees with Samson's model, even in most of the many partially occupied and split positions. The structure of β′-Mg 2Al3 is closely related to that of the β-phase. Its atomic sites can be derived from those of the β-phase by group-theoretical considerations. The main difference between the two structures is that all atomic sites are fully occupied in case of the β′-phase. The reciprocal space, Bragg as well as diffuse scattering, has been explored as function of temperature and the β- to β′-phase transition was studied in detail. The microstructures of both phases have been analyzed by electron microscopy and X-ray topography showing them highly defective. Finally, the thermal expansion coefficients and elastic parameters have been determined. Their values are somewhere in between those of Al and Mg.",

keywords = "CMA, Elastic parameters, Electron microscopy, Magnesium aluminides, Microstructure, Powder diffraction structure analysis, Samson phase, X-ray diffraction",

author = "Michael Feuerbacher and Carsten Thomas and Makongo, {Julien P.A.} and Stefan Hoffmann and Wilder Carrillo-Cabrera and Raul Cardoso and Yuri Grin and Guido Kreiner and Joubert, {Jean Marc} and Thomas Schenk and Joseph Gastaldi and Henri Nguyen-Thi and Nathalie Mangelinck-N{\"o}el and Bernard Billia and Patricia Donnadieu and Aleksandra Czyrska-Filemonowicz and Anna Zielinska-Lipiec and Beata Dubiel and Thomas Weber and Philippe Schaub and G{\"u}nter Krauss and Volker Gramlich and Jeppe Christensen and Sven Lidin and Daniel Fredrickson and Marek Mihalkovic and Wieslawa Sikora and Janusz Malinowski and Stefan Br{\"u}hne and Thomas Proffen and Wolf Assmus and {De Boissieu}, Marc and Francoise Bley and Chemin, {Jean Louis} and J{\"u}rgen Schreuer and Walter Steurer",

year = "2007",

doi = "10.1524/zkri.2007.222.6.259",

language = "English",

volume = "222",

pages = "259--288",

journal = "Zeitschrift fur Kristallographie",

issn = "0044-2968",

publisher = "De Gruyter",

number = "6",

}

Feuerbacher, M, Thomas, C, Makongo, JPA, Hoffmann, S, Carrillo-Cabrera, W, Cardoso, R, Grin, Y, Kreiner, G, Joubert, JM, Schenk, T, Gastaldi, J, Nguyen-Thi, H, Mangelinck-Nöel, N, Billia, B, Donnadieu, P, Czyrska-Filemonowicz, A, Zielinska-Lipiec, A, Dubiel, B, Weber, T, Schaub, P, Krauss, G, Gramlich, V, Christensen, J, Lidin, S, Fredrickson, D, Mihalkovic, M, Sikora, W, Malinowski, J, Brühne, S, Proffen, T, Assmus, W, De Boissieu, M, Bley, F, Chemin, JL, Schreuer, J & Steurer, W 2007, 'The Samson phase, β-Mg₂Al₃, revisited', Zeitschrift fur Kristallographie, vol. 222, no. 6, pp. 259-288. https://doi.org/10.1524/zkri.2007.222.6.259

TY - JOUR

T1 - The Samson phase, β-Mg2Al3, revisited

AU - Feuerbacher, Michael

AU - Thomas, Carsten

AU - Makongo, Julien P.A.

AU - Hoffmann, Stefan

AU - Carrillo-Cabrera, Wilder

AU - Cardoso, Raul

AU - Grin, Yuri

AU - Kreiner, Guido

AU - Joubert, Jean Marc

AU - Schenk, Thomas

AU - Gastaldi, Joseph

AU - Nguyen-Thi, Henri

AU - Mangelinck-Nöel, Nathalie

AU - Billia, Bernard

AU - Donnadieu, Patricia

AU - Czyrska-Filemonowicz, Aleksandra

AU - Zielinska-Lipiec, Anna

AU - Dubiel, Beata

AU - Weber, Thomas

AU - Schaub, Philippe

AU - Krauss, Günter

AU - Gramlich, Volker

AU - Christensen, Jeppe

AU - Lidin, Sven

AU - Fredrickson, Daniel

AU - Mihalkovic, Marek

AU - Sikora, Wieslawa

AU - Malinowski, Janusz

AU - Brühne, Stefan

AU - Proffen, Thomas

AU - Assmus, Wolf

AU - De Boissieu, Marc

AU - Bley, Francoise

AU - Chemin, Jean Louis

AU - Schreuer, Jürgen

AU - Steurer, Walter

PY - 2007

Y1 - 2007

N2 - The Al-Mg phase diagram has been reinvestigated in the vicinity of the stability range of the Samson phase, β-Mg2Al3 (cF1168). For the composition Mg38.5Al61.5, this cubic phase, space group Fd3̄m (no 227), a = 28.242(1) Å, V = 22526(2) Å3, undergoes at 214°C a first-order phase transition to rhombohedral β′-Mg2Al3, (hR293), a = 19.968(1) Å, c = 48.9114(8) Å, V = 16889(2) Å3, (i.e. 22519 Å3 for the equivalent cubic unit cell) space group R3m (no 160), a subgroup of index four of Fd3̄m. The structure of the β-phase has been redetermined at ambient temperature as well as in situ at 400°C. It essentially agrees with Samson's model, even in most of the many partially occupied and split positions. The structure of β′-Mg 2Al3 is closely related to that of the β-phase. Its atomic sites can be derived from those of the β-phase by group-theoretical considerations. The main difference between the two structures is that all atomic sites are fully occupied in case of the β′-phase. The reciprocal space, Bragg as well as diffuse scattering, has been explored as function of temperature and the β- to β′-phase transition was studied in detail. The microstructures of both phases have been analyzed by electron microscopy and X-ray topography showing them highly defective. Finally, the thermal expansion coefficients and elastic parameters have been determined. Their values are somewhere in between those of Al and Mg.

AB - The Al-Mg phase diagram has been reinvestigated in the vicinity of the stability range of the Samson phase, β-Mg2Al3 (cF1168). For the composition Mg38.5Al61.5, this cubic phase, space group Fd3̄m (no 227), a = 28.242(1) Å, V = 22526(2) Å3, undergoes at 214°C a first-order phase transition to rhombohedral β′-Mg2Al3, (hR293), a = 19.968(1) Å, c = 48.9114(8) Å, V = 16889(2) Å3, (i.e. 22519 Å3 for the equivalent cubic unit cell) space group R3m (no 160), a subgroup of index four of Fd3̄m. The structure of the β-phase has been redetermined at ambient temperature as well as in situ at 400°C. It essentially agrees with Samson's model, even in most of the many partially occupied and split positions. The structure of β′-Mg 2Al3 is closely related to that of the β-phase. Its atomic sites can be derived from those of the β-phase by group-theoretical considerations. The main difference between the two structures is that all atomic sites are fully occupied in case of the β′-phase. The reciprocal space, Bragg as well as diffuse scattering, has been explored as function of temperature and the β- to β′-phase transition was studied in detail. The microstructures of both phases have been analyzed by electron microscopy and X-ray topography showing them highly defective. Finally, the thermal expansion coefficients and elastic parameters have been determined. Their values are somewhere in between those of Al and Mg.

KW - CMA

KW - Elastic parameters

KW - Electron microscopy

KW - Magnesium aluminides

KW - Microstructure

KW - Powder diffraction structure analysis

KW - Samson phase

KW - X-ray diffraction

UR - http://www.scopus.com/inward/record.url?scp=34249817074&partnerID=8YFLogxK

U2 - 10.1524/zkri.2007.222.6.259

DO - 10.1524/zkri.2007.222.6.259

M3 - Review article

AN - SCOPUS:34249817074

SN - 0044-2968

VL - 222

SP - 259

EP - 288

JO - Zeitschrift fur Kristallographie

JF - Zeitschrift fur Kristallographie

IS - 6

ER -