A method for synthesizing soft-hard exchange coupled magnets by chemical co-precipitation molten salt method

A chemical co-precipitation and exchange coupling technology, which is applied in the field of chemical co-precipitation molten salt method to synthesize soft-hard exchange coupling magnets, can solve the problems of difficult to obtain composite magnets with good exchange coupling effects, limited mixing uniformity, and final product two-dimensionality. Solve problems such as phase composition deviation, achieve the effect of simple and easy process, and promote low-temperature synthesis of phases

Active Publication Date: 2022-01-07
南京睿磐内尔环保复合新材料有限公司
View PDF3 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The problem is that the loss of materials and the introduction of impurities during the ball milling process often lead to the deviation of the two-phase composition of the final product. In addition, the heat treatment synthesis process is limited by the uniformity of the mixture, and it is difficult to obtain a composite magnet with a good exchange coupling effect.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • A method for synthesizing soft-hard exchange coupled magnets by chemical co-precipitation molten salt method
  • A method for synthesizing soft-hard exchange coupled magnets by chemical co-precipitation molten salt method
  • A method for synthesizing soft-hard exchange coupled magnets by chemical co-precipitation molten salt method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0037] Soft-hard exchange coupled magnet xCoFe 2 o 4 CoFe in / yBaM 2 o 4 Synthesis with BaM component ratio x:y=2:1: According to the stoichiometric ratio, weigh barium nitrate, ferric nitrate nonahydrate, and cobalt nitrate hexahydrate, dissolve them in deionized water, stir and dissolve until clear and transparent, and obtain mixed metal salts Solution, wherein the iron ion concentration is 0.5mol / L; With sodium hydroxide and sodium carbonate as precipitant, add deionized water, prepare precipitant solution wherein the concentration of sodium hydroxide is 5.0mol / L, and the concentration of sodium carbonate is 0.1mol / L; and under the condition of rapid stirring, the initial metal ion solution obtained in 1) is added to the precipitant solution, and the flow rate is controlled at 200~500ml / min; after stirring and reacting for 2~6 hours, separate by suction filtration, and use Wash with deionized water until the filtrate is neutral to obtain a filter cake; the obtained filt...

Embodiment 2

[0040] Soft-hard exchange coupled magnet xCoFe 2 o 4 CoFe in / yBaM 2 o 4 Synthesis with BaM component ratio x:y=1:2: According to the stoichiometric ratio, weigh barium nitrate, ferric nitrate nonahydrate, and cobalt nitrate hexahydrate and dissolve them in deionized water, stir and dissolve until clear and transparent, and obtain mixed metal salts Solution, wherein the iron ion concentration is 0.5mol / L; With sodium hydroxide and sodium carbonate as precipitant, add deionized water, prepare precipitant solution wherein the concentration of sodium hydroxide is 5.0mol / L, and the concentration of sodium carbonate is 0.2mol / L; and under the condition of rapid stirring, the initial metal ion solution obtained in 1) is added to the precipitant solution, and the flow rate is controlled at 200~500ml / min; after stirring and reacting for 2~6 hours, separate by suction filtration, and use Wash with deionized water until the filtrate is neutral to obtain a filter cake; the obtained f...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
sizeaaaaaaaaaa
sizeaaaaaaaaaa
Login to view more

Abstract

The invention relates to the technical field of functional materials, in particular to a method for synthesizing a soft-hard exchange coupling magnet by a chemical co-precipitation molten salt method; comprising the following steps: according to xCoFe 2 o 4 CoFe in / yBaM 2 o 4 According to the stoichiometric ratio of the BaM component, the raw materials were weighed to prepare a mixed metal salt solution; to prepare a precipitant, the mixed metal salt solution was added to the precipitant, stirred and reacted for a period of time, and separated by suction filtration to obtain a filter cake; the filter cake was baked Dry to constant weight, crush and grind to obtain precursor powder, mix with salt, and ball mill to obtain mixed product; heat treat the mixed product, filter the product after cleaning, and dry the filtered product to obtain ferrite powder; The invention combines the uniform mixing of chemical co-precipitation metal ions and the crystal growth control of molten salt heat treatment, and realizes the two-component compounding of soft-hard exchange coupling magnets through technical means such as component adjustment, optimization of composite precipitant, and molten salt heat treatment instead of traditional heat treatment. Precise synthesis of ferrite and control of particle structure.

Description

technical field [0001] The invention relates to the technical field of functional materials, and relates to the preparation of composite magnetic oxides, in particular to a method for synthesizing soft-hard exchange coupling magnets by chemical co-precipitation molten salt method. Background technique [0002] M-type hexagonal barium ferrite (BaM) with hard magnetic properties has good microwave absorption properties, and is often used as an electromagnetic wave absorption magnetic loss medium. The absorption band is high and the bandwidth is narrow. Compared with BaM hard ferrite, spinel type soft ferrite is limited to lower frequency due to its lower anisotropy field. Therefore, spinel-type soft ferrite can be combined with BaM hard ferrite to reduce the magnetocrystalline anisotropy of BaM, and the exchange coupling effect of soft-hard ferrite can be adjusted by adjusting the ratio of the two-phase components in the composite system. And the polarization of the two-phas...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): C01G51/00
CPCC01G51/00C01G49/0036C01P2004/80C01P2002/72C01P2004/03C01P2004/61
Inventor 刘俊亮杨敏江辉史斌
Owner 南京睿磐内尔环保复合新材料有限公司
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products