  The potentiality of composition graded AlMgSi wires for optimized combination
of electrical conductivity and torsion strength has been investigated.
Composition graded wires were obtained by co-drawing commercially pure Al with
an AlMgSi alloy followed by diffusion annealing. Diffusion gradients and local
hardening response to precipitation treatments were evaluated thanks to
nano-indentation measurements. Resulting microstructures with spatial gradients
of nanoscaled precipitates were characterized by transmission electron
microscopy. Finally, it is shown that such graded structures give rise to an
improved combination of electrical conductivity and mechanical strength in
torsion as compared to the predictions based on a classical rule of mixture.
