Crystalline Structures of Some High Entropy Alloys Obtained by Neutron and X-Ray Diffraction

The understanding of the structure and the stability of high entropy alloys is still incomplete and the mechanisms behind the composition-property relationships are unclear. One reason is that few systematic and accurate determinations of their composition-dependent structure on atomic level have been made. In this paper some results on the structure obtained by X-ray and neutron diffraction of the CoCrFeNi alloy, to which Pd, Sn and Cu have been added in different amounts, are reported. The investigations make it obvious that none of the alloys is completely homogeneous, as has earlier been suggested, and that they do not form a perfect solid solution.