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 dimensionsUltimate tensile strength, MPaElongation, %Electrical conductivity,% IACS
UFG, diameter 20 mm, thickness 1 mm8401085
UFG, diameter 20 mm, length 100 мм6601185
UFG, diameter 5-6 mm, length > 1 m    5603083
Coarse-grained4502070

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.