Phase separation and up-hill diffusion in the ordered α2 compound of a γ- Ti-Al-Nb alloyHeike Gabrisch, Tobias Krekeler, Uwe Lorenz, Marcus Willi Rackel, Martin Ritter, Florian Pyczak and Andreas StarkMATEC Web Conf., 321 (2020) 12041DOI: https://doi.org/10.1051/matecconf/202032112041