Study of Magnetostriction in Iron and Cobalt Based Amorphous Magnetic Materials

The amorphousity of amorphous magnetic materials (cobalt-based) with composition Co_{80 - x}Fe_xB₁₀Si₁₀ (x = 0, 2, 4 and 6) has been checked by x-ray diffraction and magnetostriction, as a secondary effect, has been studied by strain gauge technique. These specimens have been prepared by melt spinning technique as a possible soft magnetic material. The effect of composition on magnetostriction has been measured with a sensitivity of 10^-6 as fractional strain. In this alloy system, the magnetic elements iron and cobalt in their pure crystalline forms have positive and negative magnetostriction respectively. It is observed that with the substitution of iron for cobalt magnetostriction has decreased gradually, which shows that iron atom has cancelled out part of the negative magnetostriction due to cobalt atoms. Since magnetoelastic effect is a property of the structure of the material and not of its chemical composition only, therefore our experimental finding is important in establishing a guideline for preparing magnetically soft amorphous material