The formation of an ultrafine-grained (UFG) state in Cu-Cr-Ag copper alloys leads to an enhancement of strength up to 840 MPa and the restoration of electrical conductivity up to  85%  of pure copper’s conductivity. The  materials that we have developed can be used for making electrical contacts and contact welding electrodes, operating at tempertures of up to 450оС

Typical structures in the UFG Cu-0.5%Cr-0.1%Ag copper alloy with an average grain size of:

(а) 200 nm; (b) 500 nm






Properties of the ultrafine-grained Cu-0.5%Cr-0.1%Ag alloy:

State and billet dimensions Ultimate tensile strength, MPa Elongation, % Electrical conductivity,% IACS
UFG, diameter 20 mm, thickness 1 mm 840 10 85
UFG, diameter 20 mm, length 100 мм 660 11 85
UFG, diameter 5-6 mm, length > 1 m     560 30 83
Coarse-grained 450 20 70

Main publications:
1.  R.K. Islamgaliev, K.M. Nesterov, G.I. Raab, R.Z. Valiev.  Cu-Cr  system  ultrafine  copper alloy and method of its production.  Russian Federation patent No. 2484175. Application date 24.10.2011. Publication date 10.06.2013.
2.  R.K.  Islamgaliev, K.M.  Nesterov, J.  Bourgon, Y.  Champion, R.Z.  Valiev. Nanostructured Cu-Cr alloy with high strength  and electrical conductivity.  J.Appl. Phys. 115, 194301 (2014).
3.  R.K. Iskamgaliev, K.M. Nesterov, R.Z. Valiev.  Structure, strength, and electric conductivity of a Cu-Cr copper-based alloy subjected to severe plastic deformation. The Physics of Metals and Metallography. 116, 2 (2015) 209-219.