A kind of preparation method of high performance soft magnetic composite material

Abstract

The invention discloses a preparing method of high-performance soft magnetism composite materials. The preparing method comprises the steps of iron powder sorting matching, insulation wrapping, pressing forming, high-temperature annealing, ternary grinding, soaking, baking and the like. High-purity water atomization iron powder and carbonyl iron powder are used for being mixed, the phenomena of a peak or double peaks can be effectively avoided, meanwhile, normal distribution is good, and the pressed density of an iron core component is effectively improved. Nanometer silicon nitride and aluminum nitride dielectric materials are used for wrapping iron powder, iron powder oxidation is effectively avoided, and eddy-current loss can be well lowered. The method is simple in preparing technology, high in efficiency and complete in wrapping, magnetic loss of the iron core component can be effectively lowered through an insulation wrapping layer on the surface of the iron powder, a prepared component is low in eddy-current loss, high in saturation flux density, high in magnetic permeability and high in specific resistance, high magnetic property and high mechanical property are achieved, and the machining method is low in cost and high in forming accuracy.

Description

technical field [0001] The invention belongs to the technical field of magnetic functional materials and powder metallurgy, and in particular relates to a preparation method of a high-performance soft magnetic composite material. Background technique [0002] Soft magnetic composite (Soft Magnetic Composite, SMC) is manufactured by powder metallurgy technology, composed of surface insulating metal powder particles (such as pure iron powder), can be pressed into parts with complex shapes in one step, and has good three-dimensional isotropy Magnetic properties, as well as low eddy current loss at medium and high frequencies, can be used as iron core materials in some motors with complex shapes and magnetic circuits and motors operating at higher frequencies. Come revolutionary change. With the development of miniaturization and high frequency of electronic devices, micro-motors, low-power motors and anti-electromagnetic interference components are widely used in automobiles, ...

AI Technical Summary

Problems solved by technology

[0003] For the existing organic-coated soft magnetic composite materials, a pressure greater than 800 MPa needs to be applied during its preparation to achieve the required compaction density, but at the same time it must satisfy good saturation magnetic induction and magnetic permeability. rate, it is necessary to anneal the soft magnetic composite material containing the organic coating layer to remove the residual stress of the material, because the organic coating layer is usually not resistant to high temperature, so it is difficult to effectively remove the residual stress

For the soft magnetic composite material of the existing inorganic cladding layer, the insulation of the cladding layer cannot meet the requirements, and the existing cladding layer containing P or S is serious to the environmental pollution, so the use of SiO 2 , MgO, SiO 2 Mixture with water, Al 2 o 3 mixed with water, ZrO 2 The inorganic insulating layer prepared by mixing with water, mica powder and water is used as the inorganic coating layer, and the inorganic insulating layer is generally stable at high temperature, which overcomes the disadvantage that the organic coating layer is usually not resistant to high temperature

However, the existing inorganic insulating layer also has disadvantages. The thermal expansion coefficient of the inorganic insulating layer and the magnetic powder differ greatly, and the thermal expansion coefficient of the inorganic insulating layer itself cannot be changed. In an environment with a large temperature difference or during long-term use, the magnetic powder will Thermal stress is generated inside, which leads to the failure of the soft magnetic composite material coated with inorganic materials to have excellent magnetic properties.

These problems restrict the development and application of soft magnetic composite materials.

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