Method for producing permanent ferrite magnet with less shrinkage

Abstract

The invention discloses a method for producing a permanent ferrite magnet with less shrinkage. The method comprises following steps: step 1), a main component is added to a ball mill and ground for 4-6 h, and slurry is obtained, wherein the main components comprise constituents in percentage by mass as follows: 10.8%-11.5% of SrCO3, 3.2%-3.7% of La2O3, 1.1%-1.4% of Co2O3 and the balance of Fe2O3,and the sum of all main components in percentage by mass is 100%; step 2), the slurry obtained in the step 1) is stirred with a wet method firstly and subjected to primary mixed grinding, obtained slurry is subjected to filter pressing by a filter press to be dewatered, and water content of the slurry is enabled to be 35%-38%; step 3), the slurry obtained in the step 2) is pumped into a rotary kiln for pre-sintering and subjected to a solid-phase reaction at the temperature of 1230-1260 DEG C, and a permanent ferrite magnet pre-sintered material is obtained; step 4), after the permanent ferrite magnet pre-sintered material obtained in the step 3) is subjected to ball milling to be coarse powder, the coarse powder and additives are mixed uniformly, a mixture is put in the ball mill for secondary fine grinding, and a dispersing agent and an emulsifier are added during secondary ball milling; step 5), fine slurry obtained in the step 4) is subjected to wet press molding, a magnetic shoe blank is obtained and sintered, and the permanent ferrite magnet is obtained.

Description

technical field [0001] The invention relates to the technical field of permanent ferrite materials, in particular to a production method of a permanent ferrite magnet with less shrinkage. Background technique [0002] Permanent magnet ferrite is currently the most widely used and produced permanent magnet material in the world, and it has been widely used in automobiles, household appliances, electrical equipment and other fields. [0003] Since the discovery of permanent magnet ferrite in the 1950s, its varieties, production methods and production technology have been greatly developed, from isotropic magnets to anisotropic magnets, from barium ferrite to strontium ferrite Body and major technological leaps from dry pressing to wet pressing. [0004] Permanent magnet ferrite has the advantages of stable magnetic properties and strong demagnetization resistance; it is not easy to rust and does not need to be coated with a protective layer; it is hard and brittle and can be ...

AI Technical Summary

Problems solved by technology

[0008] The purpose of the present invention is to solve the problems of the existing permanent ferrite magnets, such as the long sintering time of the pre-fired material in the kiln, the high energy consumption, and the poor consistency of the product performance obtained in each batch, etc., and provide short sintering time, energy A production method of permanent ferrite magnets with less shrinkage and less shrinkage, which is low in energy consumption, and has good performance consistency among batches of products.

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