TWI669153B - Magnetic powder composite material and preparation method thereof - Google Patents

Abstract

A method for preparing a magnetic powder composite material, comprising: providing a magnetic metal melt soup, the magnetic metal melt soup dropping downward; introducing a high-speed composite gas to the path of the magnetic metal melt dropping; and collecting the magnetic metal The magnetic powder composite material formed by the crushing of the molten stone by the high-speed atomizing gas. The magnetic powder composite material prepared by the method for preparing a magnetic powder composite material according to the present invention comprises: a magnetic metal powder, which is a metal material of iron samarium; and a coating film of an insulating layer, which is coated with yttrium oxide material and plated. Covering the surface of the magnetic metal powder.

Description

Magnetic powder composite material and preparation method thereof

The present invention relates to a composite material and a preparation method thereof, and more particularly to a magnetic powder composite material and a preparation method thereof.

Metal matrix composite (MMC) combines the properties of two different materials to improve the shortcomings of traditional single materials by complementing each other's defects. Its properties are determined by the properties of the base material and the covering material. In the present invention, the base material is mainly composed of a metal or alloy having magnetic properties, and the coating material coated on the surface is mainly composed of insulating properties.

The magnetic metal composite material described in the field of the invention is made by a powder metallurgy process, and the raw material mainly has a magnetic metal powder and an insulating medium. There is a uniform distribution of gaps between the magnetic metal powders inside the magnetic metal composite material. It is precisely because of the existence of these gaps that the magnetic metal composite material has a series of properties superior to other soft magnetic materials such as high electrical resistivity and low loss.

The preparation process of the magnetic metal composite material is mainly four steps: preparation of magnetic metal powder, insulation coating of magnetic metal powder, press molding and heat treatment process. The main factors affecting the magnetic properties of magnetic metal composites are: chemical composition and morphology and fineness distribution of magnetic metal powder, insulation coating of magnetic metal powder, type and amount of binder, type and amount of release agent, The size of the molding pressure, the heat treatment temperature and time, and the like.

Among them, in the atomization milling and insulation coating, there is still no good process to solve the problem of powder oxidation and pollution. The use of acid liquid for passivation insulation is not only contaminated by the magnetic metal powder itself, but also has environmental concerns; The organic resin is insulated and coated with a residue after the heat treatment and a coating process, such as how to coat a single powder to avoid agglomeration, which is also a big challenge.

The main problem to be solved by the present invention is to complete the coating of the insulating layer directly through the atomization process, thereby overcoming the problem of contamination and insulation coating of the magnetic metal composite material in the process.

In order to achieve the above object, the present invention discloses a method for preparing a magnetic powder composite material, comprising: providing a magnetic metal melt soup, the magnetic metal melt soup is dripped downward; and a high-speed composite gas is introduced into the magnetic metal melt soup. a path of dripping; and collecting a magnetic powder composite formed by crushing the magnetic metal melt by the high velocity composite gas.

In one embodiment, the magnetic metal melt is a cast iron aluminum alloy melt.

In one embodiment, the high velocity composite gas comprises an inert gas and a liquid.

In the above embodiment, the liquid is an ethyl citrate alcohol solution.

In the above embodiment, the concentration of the ethyl citrate alcohol solution is between 25 and 85%.

In one embodiment, the high velocity composite gas comprises an inert gas and a gas.

In the above embodiment, the gas is carbon dioxide.

In one embodiment, the high velocity composite gas comprises an inert gas and a solid powder.

In an embodiment, the solid powder is a ceramic powder.

In one embodiment, the magnetic powder composite material prepared by the method for preparing the magnetic powder composite material comprises: a magnetic metal powder, which is a metal material of iron bismuth aluminum; and a coating film of an insulating layer, the coating material of the insulating layer is yttrium oxide material. And plating on the surface of the magnetic metal powder.

The preparation method of the magnetic metal composite material and the magnetic metal composite material prepared by the invention have the following advantages: 1. The atomization coating of the magnetic metal powder is completed at one time: using a supersonic high-speed composite gas to melt the magnetic metal In the process of the soup, the magnetic metal melt is directly coated to form an insulating layer covering the magnetic metal powder; 2. The thickness of the plating solution can be adjusted by the concentration of the plating solution: the concentration of the plating solution can be controlled to adjust the gasification. Point to change the thickness of the coating; 3. Reduce the amount of inert gas used: the vapor pressure of the insulating layer plating solution can simultaneously assist the amount of inert gas and reduce the atomization cost; 4. Eliminate the post-treatment process, pollution And loss: the magnetic metal composite material prepared by the invention can be directly pressed or prepared by 3D printing without being subjected to powder post-treatment.

1‧‧‧Magnetic metal melting soup

2‧‧‧High speed composite gas

21‧‧‧Inert gas

22‧‧‧Liquid

3‧‧‧Magnetic powder composites

30‧‧‧Magnetic metal powder

31‧‧‧Insulation coating

Preparation steps of S1~S3‧‧‧ magnetic powder composites

1 is a flow chart of a method for preparing a magnetic metal composite material according to the present invention; FIG. 2 is a schematic view showing a preparation device of the magnetic metal composite material according to the present invention; and FIG. 3 is a schematic structural view of the magnetic metal composite material according to the present invention.

The invention directly completes the coating of the insulating layer through the atomization process, and overcomes the problem of the pollution of the magnetic metal composite material in the process and the coating of the insulating layer.

1 is a flow chart of a method for preparing a magnetic metal composite according to an embodiment of the present invention, the steps of which include: Step S1: providing a magnetic metal melt soup, the magnetic metal melt dropping down; Step S2: a path of dropping a high-speed composite gas into the magnetic metal melt; and step S3: collecting a magnetic powder composite formed by impact-breaking the magnetic metal melt by the high-speed composite gas.

Please refer to FIG. 2. FIG. 2 is a schematic diagram of a preparation apparatus of the magnetic metal composite material according to the present invention.

As shown in FIG. 2, a magnetic metal melt soup 1 is provided. The periphery of the container of the magnetic metal melt 1 maintains the temperature of the magnetic metal melt 1 by using a heating coil to maintain a liquid state of the molten metal. The soup 1 dripped down through a vertical pipe.

A high-speed composite gas 2 is introduced into the path of the magnetic metal melt 1 dripping. As shown in FIG. 2, the high-speed composite gas 2 is impacted by the left and right sides toward the magnetic metal melt 1 in the form of a horizontal pipe. When it is broken, the effect of atomizing the metal melt into powder is achieved, and the high-speed composite gas 2 is formed by pre-mixing the insulating layer plating solution (liquid 22) in the horizontal pipe with an inert gas 21, thereby breaking the magnetic metal in the impact. While the molten soup 1 is atomized into a metal powder, an insulating layer coating film may be formed on the surface of the metal molten powder.

Finally, a magnetic powder composite material 3 formed by crushing the magnetic metal melt 1 by the high-speed composite gas 2 is collected, and the magnetic powder composite material 3 is configured as a metal-based magnetic metal powder 30 and plated thereon. An insulating layer plating film 31 on the surface of the magnetic metal powder 30 (shown in FIG. 3).

In one embodiment, the magnetic metal melt 1 is a cast iron aluminum alloy melt.

In one embodiment, the high velocity composite gas 2 includes an inert gas 21 and a liquid 22.

In the above embodiment, the liquid 22 is an insulating layer plating solution.

In the above embodiment, the insulating layer plating solution is an ethyl citrate alcohol solution.

In the above embodiment, the concentration of the ethyl citrate alcohol solution is between 25 and 85%.

In the embodiment of the present invention, in the process of breaking the magnetic metal melt 1 by the high-speed composite gas 2, the atomization coating can be completed at one time, that is, using the supersonic high-speed composite gas 2 (such as before carrying the nano SiO2). In the process of crushing the magnetic metal melt 1 , the magnetic metal melt 1 is directly coated to form an insulating layer coating (such as a nano SiO 2 film) coated with the magnetic metal powder.

In an embodiment of the invention, the magnetic metal composite material is prepared by using iron-bismuth aluminum (Fe-Si-Al) metal powder as a metal base: the nano SiO2 solution used as the insulating layer plating solution is configured with a weight of 100%. 65% ethyl citrate alcohol solution 60L; iron bismuth aluminum metal melting soup based on Fe: 85% ~ 90%, Si: 10% ~ 12%, Al: 2% ~ 5% ratio of 35Kg. The parameters of iron slag aluminum metal melting soup and milling are as follows: melting temperature: 1500~1800°C; preheating temperature of load bearing :: 1400~1700°C; inner diameter of guiding tube outlet: 5~8mm; initial atomizing pressure: 30~50kg/ Cm ² ; gas flow rate: 5~10M ³ /min; ethyl citrate alcohol solution flow rate: 8~12L/min; atomization milling time: 3~8min.

In one embodiment, the thickness of the coating of the insulating layer can be adjusted by the concentration of the plating solution of the insulating layer, or by controlling the concentration of the plating solution of the insulating layer (the nano SiO2 precursor solution is ethyl orthosilicate) / Alcohol mixed solution), adjust the gasification point and change the coating thickness.

The magnetic metal composite material prepared by the preparation method of the invention can reduce the use amount of the atomization inert gas due to the mixing of the inert gas and the insulating layer fluid in the high-speed composite gas in the preparation process, because the insulating layer plating solution (positive The vapor pressure of the ethyl citrate/alcohol mixed solution at the time of forming the gas can simultaneously assist the amount of the inert gas (that is, the amount of the inert gas can be reduced), reduce the atomization cost, and the preparation method of the present invention can be used in the mist. The coating operation is completed at the same time, so that the post-processing steps, pollution, and loss can be eliminated.

In one embodiment, the high velocity composite gas comprises an inert gas and an auxiliary reaction gas.

In the above embodiment, the auxiliary reaction gas is carbon dioxide.

In one embodiment, the high velocity composite gas comprises an inert gas and a solid powder.

In the above embodiment, the solid powder is a ceramic powder.

Continuing to refer to FIG. 3 , a magnetic powder composite material 3 prepared by the method for preparing a magnetic powder composite material according to the present invention comprises: a magnetic metal powder 30 made of a ferritic aluminum metal material; and an insulating layer coating film 31 , the insulating layer Coating 31 is a cerium oxide material, and is plated on the surface of the magnetic metal powder 30 made of the ferritic aluminum material.

In summary, the method for preparing the magnetic metal composite material disclosed by the present invention and the magnetic metal composite material prepared thereof have the following advantages: 1. Atomization and coating of the magnetic metal powder are completed at one time: using a supersonic high-speed composite gas (carrying the nano-SiO2 precursor solution), in the process of crushing the magnetic metal melt, directly coating the magnetic metal melt to form an insulating layer covering the magnetic metal powder (such as a nano-SiO2 film); The concentration of the plating solution of the insulating layer is adjusted by the thickness of the plating solution: by controlling the concentration of the plating solution of the insulating layer (the nano-SiO2 precursor solution is a mixture of n-decanoic acid/alcohol), adjusting the vaporization point to change the thickness of the coating; The amount of atomized inert gas used: the vapor pressure of the insulating layer plating solution (ethyl orthosilicate/alcohol mixed solution) can also assist the amount of inert gas and reduce the atomization cost when forming the gas; 4. Eliminate the post-treatment Process, pollution and loss: The magnetic metal composite material prepared by the invention can be directly pressed or prepared by 3D printing without being subjected to powder post-treatment.

The embodiments or examples of the technical means adopted by the present invention are not intended to limit the scope of the practice of the present invention. That is, the equivalent changes and modifications made in accordance with the scope of the patent application of the present invention or the scope of the invention are covered by the scope of the invention.

Claims (8)

A method for preparing a magnetic powder composite material, comprising: providing a magnetic metal melt soup, the magnetic metal melt soup dropping downward; introducing a high-speed composite gas to the path of the magnetic metal melt dropping; and collecting the magnetic metal a magnetic powder composite formed by impact crushing of the high-speed composite gas; wherein the high-speed composite gas comprises an inert gas and a liquid; and the liquid is an ethyl citrate alcohol solution. The method for preparing a magnetic powder composite according to claim 1, wherein the magnetic metal melt is a cast iron alloy melt. The method for preparing a magnetic powder composite according to claim 1, wherein the ethyl citrate alcohol solution has a concentration of between 25 and 85%. The method for preparing a magnetic powder composite according to claim 1, wherein the high-speed composite gas comprises an inert gas and an auxiliary reaction gas. The method for producing a magnetic powder composite according to claim 4, wherein the auxiliary reaction gas is carbon dioxide. The method for producing a magnetic powder composite according to claim 1, wherein the high-speed composite gas comprises an inert gas and a solid powder. The method for producing a magnetic powder composite according to claim 6, wherein the solid powder is a ceramic powder. A magnetic powder composite material prepared by the method for preparing a magnetic powder composite material according to claim 1, wherein the structure comprises: The magnetic metal powder is made of iron-iron-aluminum metal; and the insulating layer is coated, and the insulating layer is coated with yttrium oxide and plated on the surface of the magnetic metal powder.