Re-investigation of phase equilibria in the system Al-Cu and structural analysis of the high-temperature phase eta(1)-Al(1-delta)Cu
- Author(s)
- Norbert Ponweiser, Christian Lengauer, Klaus Richter
- Abstract
The phase equilibria and reaction temperatures in the system Al-Cu were re-investigated by a combination of optical microscopy, powder X-ray diffraction (XRD) at ambient and elevated temperature, differential thermal analysis (DTA) and scanning electron microscopy (SEM). A full description of the phase diagram is given. The phase equilibria and invariant reactions in the Cu-poor part of the phase diagram could be confirmed. The Cu-rich part shows some differences in phase equilibria and invariant reactions compared to the known phase diagram. A two phase field was found between the high temperature phase eta(1) and the low temperature phase eta(2) thus indicating a first order transition. In the zeta(1)/zeta(2) region of the phase diagram recent findings on the thermal stability could be widely confirmed. Contrary to previous results, the two phase field between delta and gamma(1) is very narrow. The results of the current work indicate the absence of the high temperature beta(0) phase as well as the absence of a two phase field between gamma(1) and gamma(0) suggesting a higher order transition between gamma(1) and gamma(0). The structure of To (I-43m, Cu(5)Zn(8)-type) was confirmed by means of high-temperature XRD. Powder XRD was also used to determine the structure of the high temperature phase eta(1)-Al(1-delta)Cu. The phase is orthorhombic (space group Cmmm) and the lattice parameters are a = 4.1450(1) angstrom, b = 12.3004(4) angstrom and c = 8.720(1) angstrom; atomic coordinates are given.
- Organisation(s)
- Department of Functional Materials and Catalysis, Department of Mineralogy and Crystallography
- Journal
- Intermetallics
- Volume
- 19
- Pages
- 1737-1746
- No. of pages
- 10
- ISSN
- 0966-9795
- DOI
- https://doi.org/10.1016/j.intermet.2011.07.007
- Publication date
- 2011
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 104003 Inorganic chemistry, 104011 Materials chemistry
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/61209d76-9bbb-43eb-babb-4999b99b0fa9