A considerable part of the available literature on scandium in aluminium alloys is reviewed. Experimental data and assessments of the binary Al–Sc phase diagram, a wide range of ternary Al–Sc–X phase diagrams and a few higher order phase diagrams are accounted for, with emphasis on the aluminium rich part of the diagrams. The phase which is in equilibrium with Al, Al3Sc, can form by several different mechanisms, all of which are described. The precipitation kinetics of Al3Sc in binary Al–Sc alloys are discussed, and an overview of the reported influences of ternary alloying elements on the precipitation of Al3Sc is given. The Al3Sc phase particles can serve as a grain refiner in the Al melt, a dispersoid for controlling the grain structure of the alloy and a strengthening precipitate. Several examples of these three effects are mentioned, both in binary Al–Sc alloys, and in more complex alloys. The reported effects of Sc on the precipitation behaviour in Al–Cu, Al–Mg–Si, Al–Zn–Mg and Al–Li alloys ...

http://www.arc.nucapt.northwestern.edu/refbase/files/Royset-2005.pdf

Scandium in aluminium alloys

The crystal structure of the β′ phase in Al–Mg–Si alloys

Phase relations and precipitation in Al–Mg–Si alloys with Cu additions

Emerging trends in manufacturing such as light weighting, increased performance and functionality increases the use of multi-material, hybrid structures and thus the need for joining of dissimilar materials. The properties of the different materials are jointly utilised to achieve product performance. The joining processes can, on the other hand be challenging due to the same different properties. This paper reviews and summarizes state of the art research in joining dissimilar materials. Current and emerging joining technologies are reviewed according to the mechanisms of joint formation, i.e.; mechanical, chemical, thermal, or hybrid processes. Methods for process selection are described and future challenges for research on joining dissimilar materials are summarized.

/pdf/joining-of-dissimilar-materials-5d5ghi3lwg.pdf

Joining of dissimilar materials

The double-edge effect of second-phase particles on the recrystallization behaviour and associated mechanical properties of metallic materials

Modelling of the age hardening behaviour of Al–Mg–Si alloys

Precipitation hardening, in which small particles inhibit the movement of dislocations to strengthen a metal, has long been used to improve mechanical strength, especially of aluminum alloys. The small size of precipitates and the many possible variants of the orientation relation have made their structural determination difficult. Small precipitates in commercial aluminum-magnesium-silicon alloys play a crucial role in increasing the mechanical strength of these alloys. The composition and structure of the β” phase in an aluminum-magnesium-silicon alloy, which occur as precipitates (typically 4 nanometers by 4 nanometers by 50 nanometers) and are associated with a particularly strong increase in mechanical strength, were determined. Element analysis indicates that the composition is Mg 5 Si 6 . A rough structure model was obtained from exit waves reconstructed from high-resolution electron microscopy images. The structure was refined with electron nanodiffraction data (overall R value of 3.1 percent) with the use of a recently developed least squares refinement procedure in which dynamic diffraction is fully taken into account.

https://science.sciencemag.org/content/sci/277/5330/1221.full.pdf

S. J. Andersen

Papers

The crystal structure of the β′ phase in Al–Mg–Si alloys

Modelling of the age hardening behaviour of Al–Mg–Si alloys

Structure Determination of Mg5Si6 Particles in Al by Dynamic Electron Diffraction Studies

The influence of temperature and storage time at RT on nucleation of the β phase in a 6082 Al-Mg-Si alloy

Atomic model for GP-zones in a 6082 Al-Mg-Si system