%0 journal article
%@ 0925-8388
%A Wang, L., Song, L., Stark, A., Liu, Y., Oehring, M., Lorenz, U., Pyczak, F.

%D 2019
%J Journal of Alloys and Compounds

%P 880-886 
%R doi:10.1016/j.jallcom.2019.07.121
%T Identification of Laves phases in a Zr or Hf containing γ-γ′ Co-base superalloy
%U https://doi.org/10.1016/j.jallcom.2019.07.121
 
%X ZrCo2 and HfCo2 Laves phases were found and characterized in γ-γ′ Co-base superalloys using high-energy X-ray diffraction, energy dispersive X-ray spectroscopy and transmission electron microscopy. They formed during casting and are stable during long-term annealing at 900 °C. The ZrCo2 phase with a cubic MgCu2-type structure exhibits numerous nano-twins and stacking faults, while HfCo2 has a hexagonal MgNi2-type structure instead of MgCu2-type in contrast to literature. Their chemical compositions strongly deviated from stoichiometry and significant amounts of Al and W are contained in these phases. These could affect the atomic radius ratio and valence electron concentration and thus change the structure of the Laves phases.