A complex high-temperature phase in Cu9Zr2

Cu-Zr alloys in the vicinity of Cu9Zr2 show a remarkable three-dimensional long-period superstructure based on a face centered cubic lattice. The Cu-Zr alloy is studied by electron diffraction and high resolution electron microscopy. The complete structure remains unresolved but it is suggested that the structure consists of space filling polyhedral domains limited by octahedral as well as cube planes. The periodicity along the cube directions is mostly well defined but the spacing between the octahedral (111) planes is variable and the correlation between neighbouring polyhedra is small. (author)