An alloy with the composition of 3.5%Ni-6%Si-4%Al-bal. Fe (wt.%) "Super Sendust" is the new magnetic material shows high permeability and low coercive force. This properties may come from low magnetostriction and direction ordering, with the object of developing magnetic properties and clarifying the cause of high permeability, X-ray study and measurement of magnetic properties have been performed under conditions in which Ni contents, Annealing time, annealing temperature, texture coefficient and grain size are accepted as variables.
In this study specimens were made by rapid-solidification process. This RSP technique is available in making sheet-type specimens and very high cooling rate can be easily attained.
The experimental results obtained are summarized as follows;
(1) The Super sendust alloy was annealed at 1200℃ for 2hr in hydrogen and cooled to room temp. at a rate 1.4℃/S. The magnetic properties obtained were; ㎛ = 21000, Hc=0.1 Oe, $B_3 = 8000$ Gauss.
(2) The effect of magnetic field cooling is drastic. By applying a magnetic field 280e during cooling from 750℃ to room temp. after annealing at 1200℃ for 2 hr, the magnetic properties obtained were; ㎛=145,000, Hc=0.04 Oe, $B_3=1,100$ Gauss.
(3) The Magnetic properties improve with increasing Annealing time and grain size.
(4) In the "Super sendust" alloy heat-treated by magnetic field coding, the drastic improvement in magnetic properties is related to the induced crystalline anisotropy, ie, direction ordering.
