An experimental characterization of texture evolution during equal channel angular extrusion (ECAE) of pure copper was conducted up to 8 passes considering an extended range of processing routes. These routes are featured by 0°, 45°, 90°, 135°, and 180° rotation about the billet longitudinal axis after each pass, and were designated as R0, R45, R90, R135, and R180, respectively. They were implemented using new die designs with the cross-section of the die channels as a 24-sided regular convex polygon and with die angle (Φ) of 90° and 120°, respectively. X-ray diffraction measurements show that for both die sets, the textures developed via the different routes all show orientation concentrations along fibers with the {111} planes parallel to the macroscopic simple shear plane and <110> directions parallel to the macroscopic simple shear direction, yet the locations and orientation densities of the main texture components vary significantly with the pass number and the processing route. After 4 to 8 passes, the texture is found to be the weakest via route R180 for both die sets, and strongest via R0 or R45. For a given route and pass number, the texture developed with Φ = 120° is generally weaker than its counterpart with Φ = 90°. These results thus confirm the general tendencies of texture development in face-centered cubic metals with {111}<110> slip as the dominant deformation mechanisms, albeit in a wide range of processing route or deformation history.
Microstructure evolution during semi continuous equal channel angular extrusion process of interstitial- free steel