INFLUENCE OF CRYSTALLIZATION ON MAGNETIC-PROPERTIES IN CO66FE4MO2SI16B12 AMORPHOUS ALLOY

The annealing effects on the magnetic properties and structures of CO6 6Fe4Mo2Si16B12 amorphous alloy were studied by means of ballistic meth od and x-ray diffraction technique respectively. During the isothermal annealing at T-a = 460 degrees C, the initial permeability mu, of the sample increased at first, then decreased with the annealing time t(a ) and exhibited a maximum at about t(a) = 45 min. Meanwhile, it was fo und that magnetostriction lambda(s) changed with t(a) and ran through zero at about t(a) = 45 min. The x-ray diffraction results showed that the sample was still in an amorphous state in the whole 460 degrees C isothermal annealing process (t(a) = 0- 120 mini. After the annealing temperature increased to 480 degrees C, alpha-Fe(Co,Si phase began to precipitate, then. Co3Mo crystallites and other phases were formed su bsequently at 500 degrees C, The results of magnetic measurement indic ated chat the formation of any crystalline phases should lead to the d eterioration of magnetic properties.