- Complex metallic alloys
Complex metallic alloys (CMAs) are intermetallic compounds characterized by the following structural features:
- large unit cells, comprising some tens up to thousands of atoms,
- the presence of well-defined atom clusters, frequently of icosahedral point group symmetry,
- the occurrence of inherent disorder in the ideal structure.
Most physical properties of CMAs show distinct differences with respect to the behaviour of normal metallic alloys and therefore these materials possess a high potential for technological application.
Example phases are:
- ξ'-Al-Pd-Mn: 318 atoms per unit cell, face centred orthorhombic, atoms arranged in Mackay-type clusters.
- T-Mg-Al-Zn (Bergman phase): 163 atoms per unit cell, body centred cubic, atoms arranged in Bergman clusters.
- T-Al3Mn (Taylor phase): 204 atoms per unit cell, face centred orthorohombic, atoms arranged in Mackay-type clusters.
- Urban, Knut; Feuerbacher, M. (2004-03-15). "Structurally complex alloy phases". Journal of Non-Crystalline Solids (Elsevier B.V.) 334–335: 143–150. doi:10.1016/j.jnoncrysol.2003.11.029.
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