The influence of the substitution of metallic elements on the thermal stability and magnetic properties of amorphous FeBSi alloys

We have studied the effect of the substitution of metallic elements on the Curie temperature T_c induction, shape of the differential thermal analysis curve and crystallization temperature T_x, of glassy Fe₇₉B₁₆Si₅ alloys prepared by planar-flow casting. Substitutions have been made for all three (iron, boron and silicon) components of the glass. Increasing concentration of the substituting elements leads to embrittlement, notably with niobium or tantalum.

For the substitution of vanadium, chromium, niobium, manganese, molybdenum and tantalum for iron, we have obtained a linear decrease of T_c, independent of the substituted species. However, T_c increases with either nickel, tin or antimony substitution. We have found that the substitutions produce stronger effects when made for either boron or silicon. Substitutions for iron decrease the induction at 10 Oe, except for nickel, where this remains unchanged. For the crystallization temperature T_x, we have observed that all the elements lead to an increase, except for nickel, when substituted for iron. The changes in T_x are essentially related to the size effect.