Preparation method of flaky iron-silicon-aluminum magnetic powder with high magnetic conductivity

Abstract

The invention belongs to the field of wave-absorbing materials, and discloses a preparation method of flaky iron-silicon-aluminum magnetic powder with high magnetic conductivity. The preparation method comprises the following steps: selecting Fe-Si-Al magnetic powder with the particle size of 80-180 microns as raw material powder, and adding grinding balls, a solvent and magnetic powder into a stirring type ball mill, wherein the solvent is one or a mixed solvent of dimethyl formamide and dimethyl sulfoxide; heating the solvent and magnetic powder to 80 DEG C through a ball mill heating device, and then performing ball milling, keeping the temperature at 80-130 DEG C in the ball milling process, and then drying the magnetic powder obtained after ball milling is dried; and performing particle size grading and annealing treatment. According to the method, a traditional ball milling process is optimized, the radius-thickness ratio and the magnetic conductivity of the high-radius-thickness-ratio sheet-shaped magnetic powder are improved, and meanwhile, the yield of the sheet-shaped magnetic powder is greatly increased.

Description

technical field [0001] The invention relates to the field of wave-absorbing materials, in particular to a method for preparing high-permeability scaly sendust magnetic powder. Background technique [0002] With the rapid development of electronic information technology, the problems of electromagnetic compatibility and electromagnetic interference have become increasingly prominent. There are many ways to solve the electromagnetic compatibility problem of electronic products, such as reasonable wiring, filtering, shielding and other measures. The wave-absorbing magnetic sheet material is a flexible thin sheet material mainly composed of scaly soft magnetic alloy magnetic powder and polymer binder, also known as noise suppression sheet. In recent years, microwave-absorbing magnetic sheets are more and more favored by electronic engineers due to their high magnetic permeability and ease of use. More and more wave-absorbing magnetic sheet materials are used in electronic produ...

AI Technical Summary

Problems solved by technology

Therefore, the scale-like sendust magnetic powder after ball milling is very uneven, and there are few magnetic powders with high diameter-thickness ratio (the ratio of the diameter dimension of the scale-like magnetic powder to the thickness direction dimension), and the yield is low.

At the same time, the edge of the magnetic powder is not smooth enough, with burrs, which greatly affects the magnetic permeability of the magnetic powder

In addition, in order to improve the efficiency of ball milling and promote the deformation of sendust magnetic powder, it is usually necessary to add auxiliary materials such as dispersant or grinding aid during the ball milling process. adversely affect

[0005] Chinese patent CN103350225A discloses a multi-stage rod milling method to flatten soft magnetic alloy magnetic powder. This method can increase the diameter-thickness ratio of the magnetic powder and improve the yield, but the production process is complicated and requires multi-stage ball milling. Long time ball milling, low production efficiency

CN104249155A discloses a multi-stage ball milling method. Compared with the traditional process, the flattening rate of magnetic powder has been significantly improved. However, multi-stage ball milling is also required in this process. The ball milling time is longer, the production efficiency is lower, and precision is required. Control the process parameters, otherwise it will seriously affect the flattening rate of magnetic powder

In summary, the traditional flake-like sendust magnetic powder preparation process still has problems such as low yield and shape defects, and it is urgent to find an efficient preparation method of scaly sendust magnetic powder

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