Regensburg 2019 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

MM: Fachverband Metall- und Materialphysik

MM 14: Topical session (Symposium MM): High entropy and compositionally complex alloys

MM 14.5: Topical Talk

Dienstag, 2. April 2019, 11:45–12:15, H43

Bulk and grain boundary diffusion in high entropy alloys — •Mayur Vaidya, Sandipan Sen, Marcel Glienke, Daniel Gartner, Gerhard Wilde, and Sergiy Divinski — Institute of Materials Physics, University of Münster, Wilhelm-Klemm-Str. 10, 48149 Münster, Germany

An intriguing aspect of High entropy alloys (HEAs) is their diffusion behaviour and there is yet a lack of consensus on the factors governing atomic transport rates in HEAs. The present talk attempts to provide a critical analysis of the diffusion measurements reported so far for HEAs and gives glimpses of current diffusion studies being performed at the research lab of University of Münster. The anticipated *sluggish* diffusion is clearly absent in FCC CoCrFeNi and CoCrFeMnNi HEAs, both in the lattice and along grain boundaries. Ni is slowest diffusing species in both the HEAs, while Mn diffusion is fastest in the quinary HEA. The diffusion rates are lower (by maximum an order of magnitude) in these HEAs when compared to lower component alloys only when a homologous temperature scale is used for the comparison. Diffusivity measurements in single crystals of these HEAs have hinted towards a possible contribution of dislocations to the penetration profile. The preliminary results of solute diffusion in HCP HEAs are also presented.