IMPROVEMENT OF SOFT-MAGNETIC PROPERTIES B Y CR ADDITION FOR FE-(34-SIMILAR-TO-46)MASS-PERCENT-NI ALLOYS

It is generally understood that the soft magnetic properties of Permal loy, especially permeability, decrease with decreasing Ni content. Man y investigations have been carried out to improve the soft magnetic pr operties of Permalloy containing less than 50 mass%Ni. For example, th e effects of addition of various elements on the soft magnetic propert ies have been reported. Main purpose of the present paper is to study the mechanism on improvement of soft magnetic properties of Fe-(34 sim ilar to 46)mass%Ni alloys by the addition of Cr. The results obtained are summarized as follows: mu(i) and mu(L) are improved by increasing Cr content. Especially, the effect of Cr addition is remarkable for Ni content between 35 and 38 mass%. The improvement of soft magnetic pro perties by the addition of Cr is contributed to the decrease in K-1 an d lambda with increasing Cr content. Moreover, it is considered that t he remarkable improvement of mu(i) and mu(L) by the addition of Cr mor e than 8 mass% for Ni content between 35 and 38 mass% is due to Hopkin son effect, because T-c of the alloys are just above room temperature.