Glass Formability and Soft Magnetic Properties of Bulk Y-Fe-B-Ti Metals

The Ti effects on the glass forming ability and the magnetic properties of Y-Fe-B-Ti bulk metallic glasses have been investigated.Substituting 2 and 4 at% Ti for Fe or B in Y_6Fe_ 70B_ 22 alloys decrease the saturation magnetization(σ_s)and deteriorate the glass forming ability,respectively.However,substitution of 2 at% Ti for Y in Y_6Fe_ 72B_ 22 alloy induces larger supercooled region of 72.7℃,which not only makes the bulk glassy rod as large as 3mm in diameter,but also results in the superior soft magnetic properties of σ_s=126emu/g,coercivity(H_c)=0.2 Oe and Curie temperature(T_C)=268℃.Among all Y-Fe-B-Ti bulk amorphous rods,Y_4Fe_ 72B_ 22Ti_2 displays the best glass forming ability and also the proper soft magnetic properties.

Magnetic field characteristics analysis of a single assembled magnetic medium using ANSYS software

The section shape of an assembled magnetic medium is the most important structural parameter of a high gradient magnetic separator, which directly affects the induction distribution and magnetic field gradient of the magnetic separator. In this study, equilateral triangle, square, hexagonal, octagon, dodecagon, and round shape sections of the assembled magnetic medium are chosen to study their influence on magnetic field distribution characteristics using the ANSYS analysis. This paper utilizes a single assembled magnetic medium to understand the relationship between the geometry of the assembled magnetic medium and its magnetic field distribution characteristics. The results show that high magnetic field,regional field, magnetic field gradient, and magnetic force formed by the different sections of the assembled magnetic medium in the same background magnetic field reduce in turn based on the triangle,square, hexagonal, octagon, dodecagon, and round. Based on the magnetic field characteristics analytic results, the magnetic separation tests of the ilmenite are carried out. The results indicate that the section shape of the toothed plate compared with the section shape of cylinder can improve the recovery of ilmenite up to 45% in the same magnetizing current condition of 2A, which is consistent with magnetic field characteristics analysis of different assembled magnetic medium section shapes.

Microwave magnetic properties of soft magnetic thin films

We review our works that focus on the microwave magnetic properties of metallic, ferrite and granular thin films. Soft magnetic material with large permeability and low energy loss in the GHz range is a challenge for the inforcom technologies. GHz magnetic properties of the soft magnetic thin films with in-plane anisotropy were investigated. It is found that several hundreds of permeability at the GHz frequency was achieved for Col00_xZrx and Co90Nbl0 metallic thin films because of their high satu- ration magnetization, and an adjustable resonance frequency from 1.3 to 4.9 GHz was obtained. Compared with the metallic thin films, the weaker saturation magnetization of Ni-Zn ferrite thin films results in several tens of permeability at the GHz frequency, but the larger resistivity of the ferrite prepared in situ without any heating treatments has lower energy loss. In order to obtain materials with large permeability and low energy loss in the GHz range, the [CoFe-NiZn ferrite] composite granular thin films were investigated, where the advantage of higher saturation magnetization for the metallic alloy and the high resis- tivity as well as high saturation magnetization for the ferrite results in a good GHz magnetic performance.