Search

CN-122000187-A - Modified iron-nickel magnetic powder core and preparation method and application thereof

CN122000187ACN 122000187 ACN122000187 ACN 122000187ACN-122000187-A

Abstract

The invention relates to a modified iron-nickel magnetic powder core, a preparation method and application thereof, wherein the preparation method comprises the steps of placing the iron-nickel magnetic powder core subjected to insulating coating and annealing treatment into an acid solution, standing, and enabling the surface of the iron-nickel magnetic powder core to react with the acid solution to generate a salt mixture coating layer, so as to obtain the modified iron-nickel magnetic powder core. According to the invention, an acid washing method is adopted to carry out surface treatment on the iron-nickel magnetic powder core subjected to insulating coating and annealing treatment, an acid solution is utilized to react with metal elements on the surface of the iron-nickel magnetic powder core to generate a salt mixture coating layer containing iron and nickel, and the existence of the coating layer plays an insulating role, so that the resistance of the iron-nickel magnetic powder core can be improved, the loss can be reduced, the performance of the modified iron-nickel magnetic powder core can be obviously improved, and the conditions that the iron-nickel magnetic powder core cannot be normally used due to low surface resistance and high loss caused by decomposition of an insulating layer due to incomplete insulating coating or insufficient atmosphere protection due to over high heat treatment temperature and the like are avoided.

Inventors

  • ZHOU WEIBO
  • LI JIASONG
  • CHEN ZECONG

Assignees

  • 深圳市铂科新材料股份有限公司
  • 河源市铂科新材料有限公司

Dates

Publication Date
20260508
Application Date
20241101

Claims (10)

  1. 1. The preparation method of the modified iron-nickel magnetic powder core is characterized by comprising the following steps of: And placing the iron-nickel magnetic powder core subjected to insulating coating and annealing treatment into an acid solution, standing, and enabling the surface of the iron-nickel magnetic powder core to react with the acid solution to generate a salt mixture coating layer, so as to obtain the modified iron-nickel magnetic powder core.
  2. 2. The method according to claim 1, wherein the surface resistance of the iron-nickel magnetic powder core after the insulating coating and annealing treatment is <2kΩ; preferably, the loss of the iron-nickel magnetic powder core after the insulating coating and annealing treatment is 500-550kW/m 3 .
  3. 3. The method of manufacturing according to claim 1 or 2, wherein the surface resistance of the modified iron-nickel magnetic powder core is 20kΩ -1000kΩ; preferably, the loss of the modified iron-nickel magnetic powder core is 400-495kW/m 3 .
  4. 4. A method of preparation according to any one of claims 1 to 3, wherein the acid solution has a pH of 1 to 4; preferably, the acid solution comprises any one or a combination of at least two of nitric acid, phosphoric acid, hydrochloric acid or sulfuric acid.
  5. 5. The process according to any one of claims 1 to 4, wherein the temperature of the reaction is 20 ℃ to 80 ℃; preferably, the reaction time is 1min-20min.
  6. 6. The method according to any one of claims 1 to 5, wherein the thickness of the salt mixture coating layer is 0.5 μm to 10 μm; preferably, the composition of the salt mixture coating comprises a mixture of iron and nickel salts.
  7. 7. The method according to any one of claims 1 to 6, further comprising washing and drying after the completion of the reaction; preferably, the cleaning comprises immersing the surface of the iron-nickel magnetic powder core after the reaction by adopting deionized water; preferably, the time of the washing is 1s-300s; Preferably, the temperature of the drying is 60 ℃ to 100 ℃.
  8. 8. The preparation method according to claim 1, characterized in that the preparation method comprises the steps of: After insulating coating and annealing temperature treatment, placing the iron-nickel magnetic powder core with the surface resistance of less than 2KΩ and the loss of 500-550kW/m 3 into an acid solution with the pH value of 1-4, standing, enabling the surface of the iron-nickel magnetic powder core to react with the acid solution at 20-80 ℃ for 1-20 min, generating a ferric salt and nickel salt mixture coating layer with the thickness of 0.5-10 μm, soaking the surface of the reacted iron-nickel magnetic powder core for 1s-300s by deionized water, drying at 60-100 ℃, and removing the deionized water remained on the surface to obtain the modified iron-nickel magnetic powder core with the surface resistance of 20KΩ -1000KΩ and the loss of 400-495kW/m 3 .
  9. 9. A modified iron-nickel magnetic powder core, characterized in that it is prepared according to the preparation method of any one of claims 1-8.
  10. 10. The application of the modified iron-nickel magnetic powder core is characterized in that the modified iron-nickel magnetic powder core prepared by the preparation method of any one of claims 1-8 or the modified iron-nickel magnetic powder core of claim 9 is applied to electronic components; preferably, the electronic component includes any one of an inductor, a filter, or a transformer.

Description

Modified iron-nickel magnetic powder core and preparation method and application thereof Technical Field The invention relates to the technical field of iron-nickel magnetic powder cores, in particular to a modified iron-nickel magnetic powder core, a preparation method and application thereof. Background The metal magnetic powder core is used as a novel soft magnetic material, is widely applied to inductors, reactors and transformers, and is an indispensable product of electronic materials. With the development of electronic equipment to high frequency and miniaturization, the requirements on the metal magnetic powder core are higher and higher, and the metal magnetic powder core is particularly required to have high surface resistance, low loss and high saturation induction intensity like a soft magnetic product. Of these, iron-nickel alloy magnetic powder cores are the material of choice in many high performance applications due to their excellent physical properties, such as high magnetic permeability, high electrical resistivity, low hysteresis, and low eddy current loss. At present, the preparation of the iron-nickel metal magnetic powder core is more studied, in the preparation process of the iron-nickel metal magnetic powder core, the magnetic powder core is generally subjected to insulating coating and high-temperature annealing treatment, and in order to improve the magnetic permeability of the iron-nickel magnetic powder core, the heat treatment temperature is generally required to be increased to be higher than 600 ℃ so as to obtain higher magnetic permeability. However, the preparation method still has the following problems that firstly, the insulation coating is not matched with the corresponding preparation process, so that the insulation coating of the magnetic powder core is incomplete, the problems of low surface resistance and high loss are easy to occur, secondly, the heat treatment temperature is too high or the atmosphere protection is insufficient, and the like, so that the coated insulation film is decomposed, the problems of low surface resistance and high loss are also caused, further, the annealed iron-nickel magnetic powder core product cannot be normally used, and the iron-nickel material has high manufacturing cost due to the high price of raw materials, and when the corresponding iron-nickel magnetic powder core product cannot be used due to poor performance, only scrapping treatment can be selected, so that the scrapping cost is high. In the existing preparation process, paint such as epoxy resin is sprayed after insulating material coating and annealing treatment to coat the surface of an iron-nickel alloy soft magnetic material, for example, CN106205929A discloses a preparation method of an iron-nickel metal magnetic powder core, which comprises (1) smelting and pulverizing, (2) particle size combination, (3) magnetic powder ball milling, (4) heat treatment, (5) chemical coating, (6) oxidation film forming, (7) secondary insulating coating, (8) press molding, (9) magnetic core annealing, and (10) spray painting, wherein after the coating and the magnetic core annealing, a magnetic core finished product is obtained by a mode of solidification after the spray painting, for example, CN102306528A discloses an iron-nickel alloy soft magnetic material with magnetic permeability of mu=125 and a preparation method thereof, and the preparation method comprises (1) powder preparation, (2) powder parching, (3) press molding, (4) heat treatment, (5) surface coating, and the iron-nickel alloy soft magnetic material is obtained by coating the surface of the iron-nickel alloy soft magnetic material by adopting epoxy resin paint after the heat treatment. Therefore, in the existing preparation process of the iron-nickel metal magnetic powder core, even if the surface of the iron-nickel alloy soft magnetic material coated with the insulating material and annealed is treated, the surface of the iron-nickel alloy soft magnetic material is further physically coated with paint, so that the iron-nickel alloy soft magnetic powder core has the functions of insulating, pressure resistance and rust resistance, but the resistance and loss of the magnetic core cannot be changed. In addition, for the iron-nickel metal magnetic powder core which is not completely coated with the insulation or is not fully protected by the heat treatment (annealing) at the temperature of more than 600 ℃ and the atmosphere, the surface resistance is low, the loss is high and the iron-nickel metal magnetic powder core cannot be normally used, the existing physical coating method cannot be used for modifying the iron-nickel metal magnetic powder core, so that the iron-nickel metal magnetic powder core can be normally used. Therefore, how to provide a simple method for modifying the iron-nickel metal magnetic powder core with low surface resistance and high loss due to the decomposition of an insulating layer caused by incom