Block amorphous/ferrite soft magnetic composite material and preparation method thereof

Abstract

The invention discloses a block amorphous / ferrite soft magnetic composite material and a preparation method for the block amorphous / ferrite soft magnetic composite material. The soft magnetic composite material is the amorphous / ferrite soft magnetic composite material having a three-dimensional honeycomb structure; a honeycomb wall structure is formed by a high-resistivity soft magnetic ferrite; the honeycomb wall ferrite encloses and completely isolates amorphous alloy soft magnetic phases which are formed by soft magnetic amorphous alloy particles in the honeycomb, so that the amorphous alloy soft magnetic phases in the honeycomb are isolated from one another; and the amorphous / ferrite soft magnetic composite material comprises 50-99 weight percent of the soft magnetic amorphous alloy particles and the balance of the soft magnetic ferrite. The preparation method comprises the following steps of: firstly, mixing the soft magnetic amorphous alloy particles with soft magnetic ferrite powder in proportion, completely coating surfaces of the soft magnetic amorphous alloy particles with the soft magnetic ferrite powder; secondly, carrying out sintering densification compound moulding on the amorphous alloy particles without crystallization by employing a discharging plasma sintering technology; and finally, carrying out de-stressing and nanometre crystallization annealing heat treatment. Compared with an amorphous alloy soft magnetic material, the block amorphous / ferrite soft magnetic composite material has the advantages that: the resistivity is remarkably improved; and the working frequency of an amorphous alloy is improved.

Description

technical field [0001] The invention relates to soft magnetic materials, in particular to a bulk amorphous / ferrite soft magnetic composite material and a preparation method thereof. technical background [0002] Magnetic materials are important basic materials in national defense and national economy. In recent years, there has been a trend of using electric drive devices and electronic control devices to realize product drive, automatic control and multi-function. One of the key core materials is soft magnetic materials. It is urgent to develop high-response, high-power-density, low-loss The soft magnetic material realizes the miniaturization and high efficiency and energy saving of the device. [0003] Soft magnetic materials mainly include metal or alloy ferromagnetic soft magnetic materials; ferrite ferrimagnetic soft magnetic materials. Metal or alloy soft magnetic materials have high high saturation magnetic induction (B s ), but its low resistivity ρ makes it produ...

AI Technical Summary

Problems solved by technology

It solves the technical problems that the insulating film is easy to be brittle, the coating is uneven, the preparation process is complicated, and the soft magnetic composite material cannot be sintered after pressing.

The problem with the composition of soft magnetic composite materials is that resins and inorganic dielectric materials lead to B s reduce

Problems in the preparation process: In order to increase the compact density, the use of a large molding pressure leads to the destruction of the insulating layer and the increase of the internal stress; in order to eliminate the internal stress, the annealing at a higher temperature leads to the softening of the organic matter and the oxidation of the iron powder

However, due to the extremely high cooling rate required for the preparation of amorphous alloys, it is mainly used in commercial and production practice in the form of strips or powders, and its application is limited.

Strips are generally wound to make iron cores, with a single structure and difficult winding

The powder is usually applied in the form of a powder core. The published data of Chinese invention patents 200510132500.1 (Antai Technology Co., Ltd.) and 200980000212.7 (Hitachi Metals Co., Ltd.) show that due to the high strength and high hardness of amorphous powder, even at high pressures of 1 to 3 GPa Under molding, the filling degree of the powder core is still difficult to achieve high, and the density is usually only 5.5-5.7g / cm 3 , the saturation magnetic induction is thus reduced

At the same time reduce the magnetic permeability of the material

Amorphous soft magnetic composite materials with high density uniform and complete ferrite insulating layer have not been reported yet

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