Characteristic features of the Fe7Mo6-type structure in a transition-metal alloy examined using transmission electron microscopy

Possible structural units of the Fe7Mo6-type crystal structure in alloys, which is often called the mu structure, have been discussed on the basis of a formation process of the mu structure in an Fe-Mo alloy. A disordered decagonal-column state appeared in the initial stage where locally ordered regions of column blocks consisting of four decagonal columns existed. A column-block layer in the mu structure can also be formed by a one-dimensional connection of the same column blocks. The atomic column block can be assigned as one of the structural units in alloys.