Abstract :
The magnetization of the D03 type Heusler alloy (Fe1−xVx)3Al with compositions 0.18≤x≤0.33, has been measured at temperatures from 2 to 600 K. The Curie temperature decreases to zero as the composition approaches the x=1/3 value. The effective moment calculated from both the high temperature portion of the data utilizing a Curie–Weiss fit and from the saturation moment decreases to very near zero as the x=1/3 composition is approached. This behavior is explained by the existence of magnetic clusters of Fe atoms. Fe atoms on the V site in Fe2VAl cause the eight neighboring Fe atoms to become magnetically active thereby forming clusters of nine magnetic Fe atoms.