Schmidt, U.; Unger, R.; Gerloff, R.
Investigations of the connection between the microstructure and thermomechanical
properties in structured AlCu-based alloys.
Schmidt, U.; Unger, R., Gerloff, R.: Investigations of the connection
between the microstructure and thermomechanical properties in structured
AlCu-based alloys.
Journal of Materials Science 30 (1995) 3265–3273,
DOI: 10.1007/BF01209248.
A description is given of the structure and precipitation sequence of AlCu4.5 alloys with a magnesium content between those of binary AlCu and quasi-binary AlCuMg alloys. For alloys with a small magnesium content (0.23wt%) these are the coherent copper-like Guinier-Preston zones and the incoherent Θ′ and Θ phases with an adequate content of dissolved magnesium, so the precipitation sequence can be essentially realized without any difficulty. In the case of higher magnesium concentration, a re-orientation occurs because it requires both time and energy. An undisturbed transition to the Θ(Mg) phase is impossible. The phase structure becomes more similar to that of the S phase but it is unsafe to describe it as a quasi-binary structure. The different sizes which develop between the AlCu4.5 and AlCuMg0.98 alloys are discussed.