Berlin 2015 – wissenschaftliches Programm
MM 28.28: Poster
Dienstag, 17. März 2015, 18:30–20:30, Poster E
The influence of the stacking fault energy on the microstructure evolution of severely deformed Cu-Ni alloys — •Friederike Emeis, Gerhard Wilde, Harald Rösner, and Matthias Wegner — Institut für Materialphysik, Westfälische Wilhelms-Universität Münster, D-48149
Copper and nickel are completely miscible in the liquid and solid state forming face-centered cubic alloys. The microstructure evolution of different compositions (10/90, 50/50 and 90/10) was investigated after severe plastic deformation using high pressure torsion (HPT) followed by annealing. The grain size is thus reduced and the hardness increases. This microstructure evolution is influenced by the stacking fault energy (SFE). The SFE indicates how easily dislocations can form, which are required to operate for an easy plastic flow of the material. Other factors, such as precipitation hardening, can be neglected due to the complete miscibility. The grain size distributions, twin densities, dislocation densities and hardness were characterized using electron backscatter diffraction (EBSD) and Vickers Hardness measurements. The SFEs of the different alloys were experimentally determined by the dissociation width of the present dislocations using transmission electron microscopy (TEM). The obtained results are discussed.