The crystal structure of ζ1-Al3Cu4

Phase transformations and phase stability of the AlCuFe alloys with low-Fe content

“…3(a) shows a series of high-temperature X-ray diffraction patterns for the Al 48.5 Cu 47.5 Fe 4.0 alloy, which was pre-annealed at 620 8C for 200 h. Based on the DTA and MTA measurements, this annealing at 620 8C caused the formation of the f-phase. A thorough comparison with powder diagrams generated from known structure models in the Al-Cu and the Al-Cu-Fe phase diagrams showed that the recently solved x 1 -Al 3 Cu 4 structure [24] which corresponds to the face-centered orthorhombic oF-phase of Dong et al [23], approximated the measured powder patterns at 463, 553 and 636 8C fairly well. However, this orthorhombic cell could not explain some weak reflections at low angles.…”

“…However, the exact crystallographic data such as space group, cell dimensions, and atomic coordination's of the f-Al 10 Cu 10 Fe are still unknown. Those of Al 2 Cu 3 [14][15][16]18] or Al 3 Cu 4 [23,24] were usually used Intermetallics 13 (2005) instead. The phase stability of the f-phase was investigated [5,8,9], and it was found to be stable below 650 8C.…”

“…Since the phase diagram of the Al-Cu binary system in the composition range of 0.55!X cu !0.60 (at.%) is not yet completely clarified, the alloy compositions of AlCu, Al 2 Cu 3 and Al 3 Cu 4 were found to have at least two different types of structures depending on temperature (e.g. h 1 -AlCu with an orthorhombic cell [20], h 2 -AlCu with a monoclinic structure [21]; x 1 -Al 3 Cu 4, probably being orthorhombic [23,24], x 2 -Al 3 Cu 4 , probably being monoclinic [22]; and 3 1 -Al 2 Cu 3 , unknown structure, 3 2 -Al 2 Cu 3 with a hexagonal cell [18]). The structures of some phases are still unresolved, the ternary phases c and R have not yet been defined.…”

Structurally complex metallic coatings in the Al-Cu system and their orientation relationships with an icosahedral quasicrystal

“…[1][2][3][4][5][6][7][8][9][10] This was motivated in part by the possibility of developing CMAs as new coating materials with low friction, reduced adhesion, and good corrosion resistance for technological applications. [11][12][13] Those surface properties are related to the peculiar electronic structure of CMAs characterized by a pseudogap at the Fermi level, usually associated with poor metallic behavior.…”

Organometallic Access to Intermetallic θ‐CuE2 (E = Al, Ga) and Cu1–xAlx Phases

“…[8] Gulay and Harbrecht investigated the phase changes in α-CuAl structures, for example, the orthorhombic ζ 1 -and ζ 2 -Cu 4 Al 3 phases. [9] These authors showed that the phase transformations take place at low temperatures; for example, the ζ 2 -Cu 3 Al 4-δ phase decomposes to η 2 -CuAl and ζ 1 -Cu 4 Al 3 above 400°C. [10] Other metallurgical methods include mechanical mixing of the Cu and Al metals.…”