Mechanical properties of the high-entropy alloy Ag0.5CoCrCuFeNi at temperatures of 4.2-300K

The plastic deformation behavior of the high-entropy alloy Ag0.5CoCrCuFeNi produced in an argon-arc melt is studied for the first time at low temperatures (down to 4.2 K). Lowering the temperature from 300 to 4.2K leads to an increase in the nominal yield strength from 450 to 750 MPa while the degree of plasticity of the alloy remains on the order of 30% over the entire range. The strain rate sensitivity is measured for deformations epsilon similar to 2% by strain rate cycling. Assuming thermally activated plasma deformation, the activation volume for movement of dislocations is calculated for epsilon similar to 2% and is found to vary from 122b(3) at 300K to 35b(3) at 30 K, where b is the Burgers vector. (C) 2013 AIP Publishing LLC.