Effect of Ti, V, Cr, and Mn additions on the magnetic properties of a nanocrystalline soft magnetic Fe-Zr-B alloy with high magnetic flux density

The effect of the addition of Ti, V, Cr, and Mn on the magnetic properties of a nanocrystalline soft magnetic Fe-Zr-B alloy has been investigated. The addition of the elements increases both the crystallization temperature and the grain size of alpha-Fe. After crystallization, these elements are observed in both the alpha-Fe grains and the residual amorphous matrix. It has been found that V is a useful element to control magnetostriction by keeping the saturation magnetic flux density (B-s) high. The simultaneous addition of V and Mn increases B-s. The alloys with high B-s, above 1.75 T, show good soft magnetic properties as well; the Fe90V1Zr6B3 alloy exhibits high B-s of 1.75 T and high permeability (mu e) of 31000, and the Fe89.5V0.5Mn1Zr6B3 alloy exhibits high B-s of 1.78 T and high mu e of 23000. These high B-s values are almost the same as that of a Fe-6.5 wt% Si alloy. The alloys also exhibit low core loss. Therefore, nanocrystalline Fe-V-(Mn)-Zr-B alloys are expected to be applied to power electronic devices such as power transformers. (C) 1999 American Institute of Physics. [S0021-8979(99)37308-4].