阅读说明：本技术 一种超低铁损耗铁硅铝磁芯的制备方法 (Preparation method of ultra-low iron loss iron-silicon-aluminum magnetic core ) 是由 徐杰 周福林 曾性儒 张宗仁 于 2020-06-12 设计创作，主要内容包括：本发明公开了一种超低铁损耗铁硅铝磁芯的制备方法,包括如下步骤：S1：将铁硅铝合金粉过200-300目筛后与绝缘包覆剂混合后进行绝缘包覆处理,得到混合物料Ⅰ；S2：步骤S1获得的混合物料添加耐高温粘结剂,混合均匀后获得混合物料Ⅱ；S3：将混合物料Ⅱ压制成磁芯半成品,然后进行退火处理；S4：退火处理后的磁芯半成品置于丙酮树脂中浸润,至磁芯半成品表面没有气泡为止,后烘干,最后用环氧树脂添加酚醛树脂向磁芯半成品的表面进行喷涂。本发明通过绝缘包覆剂混合后进行绝缘包覆处理,添加耐高温粘结剂,压制成型和退火处理,得到了组织均匀、高强度、高致密度和高频磁导率的铁硅铝磁芯,铁损耗进一步降低。(The invention discloses a preparation method of an iron-silicon-aluminum magnetic core with ultralow iron loss, which comprises the following steps: s1: sieving the iron-silicon-aluminum alloy powder with a 200-sand-300-mesh sieve, mixing the iron-silicon-aluminum alloy powder with an insulating coating agent, and performing insulating coating treatment to obtain a mixed material I; s2: adding a high-temperature-resistant binder into the mixed material obtained in the step S1, and uniformly mixing to obtain a mixed material II; s3: pressing the mixed material II into a magnetic core semi-finished product, and then annealing; s4: and soaking the annealed magnetic core semi-finished product in acetone resin until no air bubbles exist on the surface of the magnetic core semi-finished product, drying, and finally spraying epoxy resin and phenolic resin on the surface of the magnetic core semi-finished product. According to the invention, the iron-silicon-aluminum magnetic core with uniform structure, high strength, high density and high-frequency magnetic conductivity is obtained by mixing the insulating coating agents, then carrying out insulating coating treatment, adding the high-temperature-resistant binder, and carrying out press forming and annealing treatment, and the iron loss is further reduced.)

1. A preparation method of an ultra-low iron loss iron-silicon-aluminum magnetic core is characterized by comprising the following steps: the method comprises the following steps:

s1: the preparation method comprises the following steps of (1) sieving iron-silicon-aluminum alloy powder with a 200-inch and 300-inch sieve, mixing the iron-silicon-aluminum alloy powder with an insulating coating agent, and carrying out insulating coating treatment to obtain a mixed material I, wherein the insulating coating agent is mica powder, zinc stearate, silicone resin and kaolin, and the iron-silicon-aluminum alloy powder comprises the following components in percentage by mass: 5.0-10.0% of Si, 4-7% of Al and the balance of Fe;

s2: adding a high-temperature-resistant binder into the mixed material obtained in the step S1, wherein the high-temperature-resistant binder is water glass, potassium water glass, composite phosphate and SiO₂One or more sol with the addition of 0.5-2% is mixed evenly to obtain a mixed material II;

s3: pressing the mixed material II into a magnetic core semi-finished product, and then carrying out annealing treatment, wherein the annealing treatment is not more than 2h, and the method comprises the following specific steps: firstly, preserving heat of the magnetic core semi-finished product for 30min at the temperature of 300-350 ℃, then preserving heat for 30min at the temperature of 500 ℃, then annealing for 30min at the temperature of 750 ℃, and protecting by using the atmosphere of liquid nitrogen;

s4: and soaking the annealed magnetic core semi-finished product in acetone resin until no air bubbles exist on the surface of the magnetic core semi-finished product, drying, and finally spraying epoxy resin and phenolic resin on the surface of the magnetic core semi-finished product.

2. The method for preparing the ultra-low iron loss sendust core according to claim 1, wherein the method comprises the following steps: in the step S1, the mica powder is 10-15%, the zinc stearate is 20-36%, the silicone resin is 50-80%, and the balance is kaolin, and the insulation coating treatment specifically comprises the following steps: adding kaolin, mica powder and silicone resin into the iron-silicon-aluminum alloy powder in sequence, adding zinc stearate after uniformly stirring, and uniformly stirring.

3. The method for preparing the ultra-low iron loss sendust core according to claim 1, wherein the method comprises the following steps: the mixing temperature in the step S1 is 15-130 ℃, the mixing speed is 5-60r/min, and the mixing time is 5-80 min.

4. The method for preparing the ultra-low iron loss sendust core according to claim 1, wherein the method comprises the following steps: the preparation steps of the iron-silicon-aluminum alloy powder are as follows: smelting the iron-silicon-aluminum alloy at 1450 ℃ for 40-60 min; and introducing the alloy subjected to smelting and crushing into a ball mill for grinding, taking out powder, adding a phosphating solution for reaction, and drying.

5. The method for preparing an ultra-low iron loss sendust core according to claim 4, wherein the method comprises the following steps: the reaction time of the powder after adding the phosphoric acid solution is 1-2 hours, the drying temperature is 80-130 ℃, and the phosphating solution comprises: 0.5-1.0 percent of phosphoric acid, 98.5-97.8 percent of alcohol and the balance of chromic anhydride.

6. The method for preparing the ultra-low iron loss sendust core according to claim 1, wherein the method comprises the following steps: pressing the mixed material II into a magnetic core semi-finished product by adopting an automatic dry powder forming hydraulic press, wherein the pressing pressure is 18-20t/cm²The pressed density is 6.0-6.1g/cm³。

Technical Field

The invention belongs to the technical field of iron-silicon-aluminum magnetic cores, and particularly relates to a preparation method of an iron-silicon-aluminum magnetic core with ultralow iron loss.

Background

Magnetic core refers to a sintered magnetic metal oxide composed of various iron oxide mixtures. The sendust magnetic core is mainly applied to the high-frequency field, and currently, a magnetic core prepared by sendust has iron loss, so that the magnetic performance of sendust is poor.

Disclosure of Invention

The invention aims to solve the defects in the prior art and provides a preparation method of an iron-silicon-aluminum magnetic core with ultralow iron loss.

In order to achieve the purpose, the invention provides the following technical scheme:

a preparation method of an ultra-low iron loss iron-silicon-aluminum magnetic core comprises the following steps:

s1: the preparation method comprises the following steps of (1) sieving iron-silicon-aluminum alloy powder with a 200-inch and 300-inch sieve, mixing the iron-silicon-aluminum alloy powder with an insulating coating agent, and carrying out insulating coating treatment to obtain a mixed material I, wherein the insulating coating agent is mica powder, zinc stearate, silicone resin and kaolin, and the iron-silicon-aluminum alloy powder comprises the following components in percentage by mass: 5.0-10.0% of Si, 4-7% of Al and the balance of Fe;

s2: adding a high-temperature-resistant binder into the mixed material obtained in the step S1, wherein the high-temperature-resistant binder is water glass, potassium water glass, composite phosphate and SiO₂One or more sol with the addition of 0.5-2% is mixed evenly to obtain a mixed material II;

s3: pressing the mixed material II into a magnetic core semi-finished product, and then carrying out annealing treatment, wherein the annealing treatment is not more than 2h, and the method comprises the following specific steps: firstly, preserving heat of the magnetic core semi-finished product for 30min at the temperature of 300-350 ℃, then preserving heat for 30min at the temperature of 500 ℃, then annealing for 30min at the temperature of 750 ℃, and protecting by using the atmosphere of liquid nitrogen;

s4: and soaking the annealed magnetic core semi-finished product in acetone resin until no air bubbles exist on the surface of the magnetic core semi-finished product, drying, and finally spraying epoxy resin and phenolic resin on the surface of the magnetic core semi-finished product.

Preferably, in the step S1, the mica powder is 10 to 15%, the zinc stearate is 20 to 36%, the silicone resin is 50 to 80%, and the balance is kaolin, and the insulating coating treatment specifically includes: adding kaolin, mica powder and silicone resin into the iron-silicon-aluminum alloy powder in sequence, adding zinc stearate after uniformly stirring, and uniformly stirring.

Preferably, the mixing temperature in the step S1 is 15-130 ℃, the mixing speed is 5-60r/min, and the mixing time is 5-80 min.

Preferably, the preparation steps of the iron-silicon-aluminum alloy powder are as follows: smelting the iron-silicon-aluminum alloy at 1450 ℃ for 40-60 min; and introducing the alloy subjected to smelting and crushing into a ball mill for grinding, taking out powder, adding a phosphating solution for reaction, and drying.

Preferably, the reaction time of the powder after adding the phosphoric acid solution is 1-2 hours, the drying temperature is 80-130 ℃, and the phosphating solution comprises: 0.5-1.0 percent of phosphoric acid, 98.5-97.8 percent of alcohol and the balance of chromic anhydride.

Preferably, the mixed material II is pressed into a magnetic core semi-finished product by adopting an automatic dry powder forming hydraulic press, and the pressing pressure is 18-20t/cm²The pressed density is 6.0-6.1g/cm³。

Compared with the prior art, the invention has the beneficial effects that: compared with the prior art, the preparation method of the iron-silicon-aluminum magnetic core with ultralow iron loss, provided by the invention, has the advantages that the iron-silicon-aluminum magnetic core with uniform structure, high strength, high density and high-frequency magnetic conductivity is obtained by mixing the insulating coating agents, then carrying out insulating coating treatment, adding the high-temperature-resistant binder, and carrying out compression molding and annealing treatment, and the iron loss is further reduced.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.