Atomic structures in the amorphous Fe70M10B20 (M = Zr, M,and Cr) alloys wit
h different DeltaT(x) values were studied by the anomalous X-ray scattering
method. Their basic structural features resemble each other except a shape
of a triangular prism as a local structural unit. The prism is slightly di
storted in the amorphous Fe70M10B20 (M = Zr and Nb) alloys because a part o
f Fe atoms at the vertices are replaced by the M elements. The larger the s
ize difference between M and Fe is, the larger the dr, value becomes. This
tendency and the observations of the crystallization process by the differe
ntial scanning calorimetry and X-ray diffraction measurements indicate us a
close relationship between thermal stability of the amorphous state and th
e shape of the prism in the amorphous Fe70M10B20 alloy.