Forced volume magnetostriction

The onset of ferromagnetism in this system has usually been interpreted in terms of an environmental model. Fe atoms which occupy Al sites are surrounded by 8 Fe nearest neighbours and it is suggested that the percolation of such atoms (with pFc = 2.2pB) on Al sites eventually gives rise to ferromagnetism. The critical concentration does not appear to be significantly different for the two conditions. The forced volume magnetostriction peaks at 4 X 10 9 Oe-1 at 70% Fe for... 

The two principle modes of the magnetostriction (A -° and As or Xy-2) introduced above are illustrated in fig. 2. With respect to the non-magnetic fictitious state, a spherical, isotropic sample exhibits a relative volume change AV/V = A" 0, when it becomes magnetic. In addition, when one forces the moments to be directed along an applied magnetic field B, an anisotropic deformation is induced, which transfers the sphere into an ellipsoid with the same volume. 

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