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CN-122010547-A - Gadolinium ion doped M-type strontium ferrite wave absorbing material and preparation method and application thereof

CN122010547ACN 122010547 ACN122010547 ACN 122010547ACN-122010547-A

Abstract

A gadolinium ion doped M-type strontium ferrite wave absorbing material and a preparation method and application thereof relate to the field of electromagnetic wave absorbing materials and solve the problems that the traditional strontium ferrite has insufficient magnetic response in a Ku wave band, unbalanced magneto-electric matching and limited engineering suitability, and the traditional rare earth ion doped modified strontium ferrite is difficult to realize cooperative optimization between frequency band broadening and magnetic property stabilization, is easy to cause structural instability and magnetic property fluctuation and has complex preparation process. The chemical formula of the gadolinium ion doped M-type strontium ferrite wave absorbing material is Sr 1‑x Gd x Fe 12 O 19 , wherein x is more than or equal to 0.01 and less than or equal to 0.50, strontium carbonate, ferric oxide and gadolinium oxide are mixed and ground according to the stoichiometric ratio, presintering and heat preservation are carried out, and the presintered blocky product is ground, sintered and heat preservation is carried out, so that the gadolinium ion doped M-type strontium ferrite wave absorbing material is obtained. The invention can be applied to the preparation of a wave-absorbing coating for Ku wave band electromagnetic interference protection or the preparation of a composite wave-absorbing material with magnetic-electric cooperative loss.

Inventors

  • NIU XIAODONG
  • GAO LELE
  • ZHANG GUANGRUI
  • Niu Shixiang
  • ZHANG SU
  • LIU JINRONG

Assignees

  • 内蒙古北方稀土新材料技术创新有限公司
  • 中国科学院长春应用化学研究所

Dates

Publication Date
20260512
Application Date
20260212

Claims (10)

  1. 1. A gadolinium ion doped M-type strontium ferrite wave-absorbing material is characterized in that the chemical formula of the gadolinium ion doped M-type strontium ferrite wave-absorbing material is Sr 1-x Gd x Fe 12 O 19 , wherein x is more than or equal to 0.01 and less than or equal to 0.50.
  2. 2. The gadolinium ion doped M-type strontium ferrite wave absorbing material according to claim 1, wherein the gadolinium ion doped M-type strontium ferrite wave absorbing material has a thickness of 1-5 mm.
  3. 3. A method for preparing the gadolinium ion doped M-type strontium ferrite wave absorbing material according to claim 1 or 2, comprising the following preparation steps: mixing strontium carbonate, ferric oxide and gadolinium oxide according to the stoichiometric ratio of Sr 1-x Gd x Fe 12 O 19 , carrying out primary grinding, presintering and heat preservation, carrying out secondary grinding, sintering and heat preservation on the presintering product, and obtaining the gadolinium ion doped M-type strontium ferrite wave absorbing material.
  4. 4. The method for preparing the gadolinium ion doped M-type strontium ferrite wave absorbing material according to claim 3, wherein the particle size of the powder obtained by primary grinding is 1-6 μm.
  5. 5. The method for preparing the gadolinium ion doped M-type strontium ferrite wave absorbing material according to claim 3, wherein the presintering temperature is 1100-1500 ℃, the presintering atmosphere is air atmosphere, and the presintering temperature rising rate is 5 ℃ per minute.
  6. 6. The method for preparing the gadolinium ion doped M-type strontium ferrite wave absorbing material according to claim 3, wherein the particle size of the powder obtained by secondary grinding is 1-5 μm.
  7. 7. The preparation method of the gadolinium ion doped M-type strontium ferrite wave absorbing material is characterized in that the sintering temperature is 1100-1500 ℃, the sintering atmosphere is air, and the sintering temperature rising rate is 5 ℃ per minute.
  8. 8. The method for preparing the gadolinium ion doped M-type strontium ferrite wave absorbing material according to claim 7, wherein the presintering temperature is 50 ℃ lower than the sintering temperature at all times, and the heat preservation time is 2-5 h.
  9. 9. The application of the gadolinium ion doped M-type strontium ferrite wave-absorbing material according to claim 1 or 2 or the gadolinium ion doped M-type strontium ferrite wave-absorbing material prepared by the preparation method according to any one of claims 3 to 8, which is characterized in that the gadolinium ion doped M-type strontium ferrite wave-absorbing material is applied to the preparation of a Ku band electromagnetic interference protection wave-absorbing coating or a magneto-electric synergetic loss composite wave-absorbing material.
  10. 10. The application of the gadolinium ion doped M-type strontium ferrite wave absorbing material according to claim 9, wherein the Ku band electromagnetic interference protective wave absorbing coating is applied to the electromagnetic protection field of satellite communication terminals, radar antenna systems, 5G communication devices or electronic devices.

Description

Gadolinium ion doped M-type strontium ferrite wave absorbing material and preparation method and application thereof Technical Field The invention relates to the field of electromagnetic wave absorbing materials, in particular to a gadolinium ion doped M-type strontium ferrite wave absorbing material, a preparation method and application thereof. Background Under the background of rapid development of a 5G communication system, a high-frequency phased array radar and advanced electronic equipment, the Ku wave band (12-18 GHz) electromagnetic wave has the characteristics of short wavelength, concentrated energy, strong propagation directivity and the like, and is widely applied to the fields of satellite communication, radar detection, precision guidance and the like. The existing M-type strontium ferrite (SrFe 12O19) is considered as a potential high-frequency magnetic loss type wave absorbing material due to the high magnetocrystalline anisotropy constant and excellent chemical stability, but the natural resonant frequency of the traditional SrFe 12O19 is usually positioned in a lower frequency band, the magnetic response is insufficient in a Ku wave band range, the magnetic loss mechanism is relatively single, the ideal magnetic conductivity and dielectric constant cooperative matching is difficult to realize in a high frequency band, the absorption bandwidth is limited, and the impedance matching performance is poor. Meanwhile, when the thickness of the material is reduced to meet the light weight requirement, the reflection loss peak value is often remarkably reduced, and engineering suitability is limited. In order to improve the defects, the prior art adopts a rare earth ion doping mode to modify the strontium ferrite, and the lattice structure and magnetocrystalline anisotropy are regulated by introducing rare earth ions. However, in practical application, the occupation proportion of each ion in the crystal lattice is difficult to accurately adjust in the doping process, and excessive or insufficient ions are easy to occur, so that local lattice stress concentration, uneven oxygen vacancy distribution and fluctuation of Fe 2+/Fe3+ proportion are caused, microstructure is disordered, defects or stress distortion occur in crystal phase, magnetic moment arrangement is disordered, saturation magnetization intensity is reduced, and coercive force is unstable. For example, as disclosed in chinese patent document CN120191970a, neodymium-zirconium co-substitution strontium ferrite material, although wave absorption frequency band is widened and matching thickness is reduced by the cooperation of double ions (neodymium and zirconium), saturation magnetization and coercive force are both reduced, magnetocrystalline anisotropy is weakened, and effective magnetic moment quantity capable of participating in microwave magnetic loss in unit volume is limited. Meanwhile, due to local defects and uneven arrangement of magnetic moments of the microstructure, the material is sensitive to external electromagnetic interference and thermal disturbance, and the wave absorbing performance is difficult to keep stable under a complex working condition. Therefore, in the prior art, obvious contradiction exists between microstructure control and performance optimization in the rare earth ion doping modification process, and the balance between wave absorption frequency band broadening and magnetic property maintenance is difficult to be considered. In addition, as disclosed in Chinese patent document CN115974542A, the praseodymium-doped strontium ferrite material improves the dielectric property to a certain extent, but the preparation relies on a sol-gel method to finely control the morphology and the particle size, has sensitive technological parameters, limited repeatability and higher raw material cost, and is not beneficial to large-scale production. In addition, the partial doping system has the problems of serious lattice distortion, paraphase generation or abnormal grain growth and the like, and the microstructure problems further weaken the consistency of the magnetic performance and the engineering reliability of the material. Therefore, developing a special strontium ferrite wave-absorbing material for Ku wave bands, which has simple process and excellent performance and can effectively consider high-frequency magnetic response capability, magnetic performance stability and engineering feasibility, becomes a technical problem to be solved in the current field. Disclosure of Invention The invention provides a gadolinium ion doped M-type strontium ferrite wave absorbing material and a preparation method and application thereof, and aims to solve the problems that the traditional strontium ferrite is insufficient in magnetic response in a Ku wave band, unbalanced in magnetoelectric matching and limited in engineering suitability, and the traditional rare earth ion doped modified strontium ferrite is difficult to realiz