Influence of the External and Internal Factors on Saturation Magnetization Process for Nanocrystalline Alloy

Nanocrystalline (NC) alloy may confront saturation problems with different high-frequency operation circumstances, which are summarized as two typical situations in this paper. One case is “dynamic saturation (DS)” where the alternating magnetic field contains the weak dc biasing field. Another situation is “static saturation (SS)” where the hybrid field comprises not only the weak time-varying field but also the strong dc biasing field. The external and internal factors that affect the saturation magnetization process for the NC alloys were analyzed, under two types of saturation magnetic fields. Two parameters including the saturation time and the rotational velocity of magnetic moment were employed. The external factors, which determine the working condition of the NC alloys, are the dc biasing field and the frequency of the alternating field. The effects of the above two factors are related to the type of saturated magnetic field. In the DS field, the promoting effect of frequency increase on the magnetization process is greater than that of the biasing field, while in the SS field, the opposite is true. The internal factor, which is the grain size, is essential to the soft magnetic properties of the NC alloys. The effects of this factor are independent of the type of saturation field. Increasing the grain size of the NC alloys will delay the magnetization process.