MAGNETIC-PERMEABILITY AFTEREFFECT AND THE TRANSITION FROM CO-RICH TO FE-RICH AMORPHOUS-ALLOYS

Measurements of the after-effect of the initial magnetic permeability DELTA mu / mu , the saturation magnetostriction lambda //s, and the magnetization I//s have been performed at room temperature on Fe-rich, Co-rich and Co//7//5// minus //xFe//xSi//1//5B//1//0 (x equals 0 minus 50) amorphous alloys to study the dependence of DELTA mu / mu on the transition metal (Co-Fe). Results for Fe-rich and Co-rich alloys lie on two distinct curves. There is a transition region between these curves, corresponding to the alloys Co//7//5// minus //xFe//xSi//1//5B//1//0 (8. 5 less than x less than 35), whose nature is discussed in terms of recent theories of the magnetic after-effect.