Effects of severe plastic deformation by ECAP on the microstructure and mechanical properties of a commercial copper alloy

Abstract

This work is concerned with the comparison of the microstructural and mechanical properties changes in a low alloy copper by Equal channel angular pressing and intermediate annealing at different temperatures (room temperature, at 250 °C and 450 °C after every pass). The die channel angle used was 100°, and the back angle was 10°. We have investigated the mechanical properties of Vicker’s hardness, ultimate tensile strength (UTS), offset yielding strength (YS), percentage elongation (ef), along with the microstructural changes that produce changes in texture and resultant small sizes of grains. The processing combination of annealing at 250 °C and Route-C ECAP die extrusion results in far superior mechanical properties as compared to other treatments while generating uniformity in the microstructure. This work includes the microstructural analysis using optical microscopy, fractography images (SEM), tensile strength, and EBSD (Electron Back-scattered Diffraction) and x-ray powder diffraction. The processing combination shows outstanding promise and the annealing effects on ECAP results can be highly useful for industrial and research applications.