Speaker
Description
Single-phase multi-principal element alloys, termed as high-entropy alloys (HEAs), are in focus of an intensive research now, both for fundamental understanding and technological applictions. A “sluggish” diffusion concept [1] helped to boost an interest from many diffusion groups and to improve our knowledge on diffusion in the multicomponent alloys. In the overview, the current state-of-the-art of diffusion research in the multi-principal element alloys is presented. Whereas tracer diffusion might be considered as sluggish when the diffusion rates in FCC CoCrFeNi and CoCrFeMnNi HEAs are analysed [2-4], the concept becomes ambiguous when the element diffusivities in the FCC Ni$_x$(CoCrFeMn)$_{1-x}$ alloys are considered [5]. In HCP AlHfScTiZr HEAs, Zr diffusion is recently found [6] to be even enhanced with respect to that in pure $\alpha$-Zr even when considered at the same homologous temperatures. The origin of such behaviour is analysed. The importance of diffusion measurements using the ISOLDE facilities is highlighted.
References
[1] Yeh, J.W. Ann. Chim-Sci. Mat., 2006, 31, 633-648.
[2] Vaidya M., Trubel S., Murty B.S., Wilde G., Divinski S.V., JALCOM 688 (2016) 994.
[3] Vaidya M., Pradeep K.G., Murty B.S., Wilde G., Divinski S.V., Acta Materialia 146 (2018) 211.
[4] D. Gaertner, J. Kottke, Y. Chumlyakov, G. Wilde, S.V. Divinski, J Mater Res 33 (2018) 3184.
[5] J. Kottke, M. Laurent-Brocq, A. Fareed, D. Gaertner, L. Perrière, L. Rogal, S.V. Divinski, G.Wilde, Scripta Materialia 159 (2018) 94.
[6] M. Vaidya, S. Sen, X. Zhang, L. Frommeyer, L. Rogal, S. Sankaran, B. Grabowski, G. Wilde, S. Divinski, Acta Materialia 196 (2020) 220-230.
