1988 Volume 52 Issue 7 Pages 725-732
Investigations have been made on the effect of small additions of the non-ferromagnetic elements, Cu, Ag, Al, Ti, Zr, Si, Ge, Sn, Nb, Ta, Cr, W and Mn, 2% on the magnetic properties of a 83%Ni-11%Fe-6%V alloy and the optimum short-range ordering heat treatments at low temperature to obtain high permeability. Specimens used in this study were prepared from each alloy sheet less than 0.2 mm thick subjected to the various heat treatments in a pure H2 atmosphere.
In the case of the addition of each of Si, Ti, Sn, Ge, W, Nb and Ta varying from 1 or 2%, a higher value of dc initial permeability and a lower value of coercive force than those of the Ni-Fe-6%V base alloy are obtained. Mn exhibits such an advantageous characteristic effect that the lowering in saturation magnetic induction by the addition does not occur. The effective permeability μe in a higher frequency field of the base alloy can be improved by the additions of Sn, Si, Nb and Ta. Especially Sn raises remarkably the value of μe. For example, an alloy containing 2%Sn exhibits a nearly 25% higher value of μe at 100 kHz for the alloy specimen 0.025 mm in sheet thickness. The additions of the elements such as Al, Si, Ti and Mn, which are very susceptible to the oxidation, or Sn bring about the reduction in optimum duration of the ordering heat treatment for the highest permeability inversely with the amount of the additions. These two types of the shortening effect are considered to be due mainly to the generation of excess vacancies which accelerate the ordering, by the formation of the oxidized surface layer and the concentration of segregated Sn atoms on the sheet surface, respectively.
