New nanostructured metallic conductors for wires and cables with increased conductivity and improved strength characteristics
In the area of fundamentally new nanostructured metallic conductors development is a close cooperation with the collective group of researchers from the Institute of Physics of Advanced Materials, Ufa State Aviation Technical University under the guidance of prof. R.Z. Valiev, a leading scientist in Russia and in the world in the field of physical metallurgy and bulk nanostructured materials.
The use of pure metals having high electrical conductivity, it is impossible for these purposes because of their low strength.
Improving the strength of the metal due to its doping with conventional methods of alloys production leads to inevitable loss of conductivity due to scattering of electrons by impurity atoms, precipitation of new phases and other defects that arise in the alloy manufacturing process. One approach to solving this problem is applying the methods of severe plastic deformation (e.g., equal channel angular pressing in parallel channels) of metal alloys based on aluminum and copper, combined with subsequent heat treatment. Intense plastic deformation leads to the formation of ultrafine alloy structure, saturating it with grain boundaries, and with subsequent heat treatment it is possible to achieve optimal phase composition of intragranular material and composite structure of grain boundaries by allocating clusters of impurity atoms on them. Formed in a such way heterogeneous structure has enhanced strength properties due to grain refinement and the presence of precipitates of new phases within the grain and at the grain boundaries as well, and high electrical conductivity due to reducing of the concentration of impurity atoms in the solid solution of intragranular phase.
A team led by prof. R.Z. Valiev conducts research of ultrafinegrained structure formation features, mechanical properties, and the electronic conductivity of aluminum alloys of Al-Mg-Si system, subjected to intense plastic deformation.
R.Z. Valiev et al., Rev. Adv. Mater. Sci. 31 (2012)