阅读说明：本技术 超顺磁性电磁复合材料、其制备方法与高灵敏度电磁阀 (Superparamagnetism electromagnetic composite material, preparation method thereof and high-sensitivity electromagnetic valve ) 是由 张鹏 李蔚 郑文毅 于 2019-09-10 设计创作，主要内容包括：本发明提供一种超顺磁性电磁复合材料,其包括原料A和原料B,原料A为纳米四氧化三铁,原料B为环氧树脂或聚四氟乙烯；原料A的质量百分比为10％～70％。另外还提供一种该电磁复合材料的制备方法,先称取原料A和原料B,然后加入球磨机,在40～50r/min转速、10～20h内进行球磨混合均匀,然后放进模具在5～25MPa的成型压力下压制成型,完毕,在180℃～360℃温度下进行90～120min的固化反应,以获得超顺磁性电磁复合材料。除此还提供一种高灵敏度电磁阀,采用以上所述的制备方法来制备该电磁阀的具有超顺磁性的静铁芯和动铁芯,可解决现有传统电磁阀中电磁铁存在滞后而导致灵敏度无法提高的问题。(The invention provides a superparamagnetic electromagnetic composite material, which comprises a raw material A and a raw material B, wherein the raw material A is nano ferroferric oxide, and the raw material B is epoxy resin or polytetrafluoroethylene; the mass percentage of the raw material A is 10-70%. And in addition, a preparation method of the electromagnetic composite material is also provided, and the raw material A and the raw material B are weighed firstly, then added into a ball mill, ball-milled and mixed uniformly at the rotating speed of 40-50 r/min for 10-20 h, then put into a mould to be pressed and formed under the forming pressure of 5-25 MPa, and after the completion, the curing reaction is carried out at the temperature of 180-360 ℃ for 90-120 min, so that the superparamagnetic electromagnetic composite material is obtained. The preparation method is adopted to prepare the static iron core and the movable iron core with superparamagnetism of the electromagnetic valve, and the problem that the sensitivity cannot be improved due to hysteresis of the electromagnet in the conventional electromagnetic valve can be solved.)

1. A superparamagnetic electromagnetic composite material is characterized by comprising a raw material A and a raw material B, wherein the raw material A is nano ferroferric oxide, and the raw material B is epoxy resin or polytetrafluoroethylene; according to the mass percentage, the nano ferroferric oxide accounts for 10-70%.

2. The superparamagnetic electromagnetic composite material according to claim 1, wherein said nano ferroferric oxide is 50% by mass.

3. A method for the preparation of an electromagnetic composite material according to claim 1 or 2, characterized in that it comprises the steps of:

s100: weighing a raw material A and a raw material B;

s200: respectively adding the weighed raw material A and the weighed raw material B into a ball mill for ball milling and mixing;

S300: after ball milling and mixing, putting the uniformly mixed raw materials into a die, and performing compression molding to obtain a green body;

S400: and carrying out a curing reaction on the obtained green body to obtain the superparamagnetic electromagnetic composite material.

4. The method for preparing an electromagnetic composite material according to claim 3, wherein the ratio of the ball milling media added by the ball mill to the total amount of the raw material A and the raw material B is 1: 1.

5. the method of making an electromagnetic composite material as set forth in claim 4 wherein the ball milling media is zirconia milling balls.

6. the preparation method of the electromagnetic composite material according to claim 3, wherein the rotation speed of the ball mill is 40-50 r/min, and the ball milling time is 10-20 h.

7. The method for preparing the electromagnetic composite material according to claim 3, wherein the particle size of the raw material A is 10-30 nm.

8. the method of preparing an electromagnetic composite material as claimed in claim 3, wherein the green body forming pressure is 5 to 25 MPa.

9. the method for preparing the electromagnetic composite material according to claim 3, wherein the curing reaction temperature is 180-360 ℃ and the curing time is 90-120 min.

10. A high-sensitivity electromagnetic valve characterized by being provided with a stationary iron core and a movable iron core made of the electromagnetic composite material as recited in claim 1 or 2.

Technical Field

The invention belongs to the technical field of composite materials, and particularly relates to a superparamagnetic electromagnetic composite material, a preparation method thereof and a high-sensitivity electromagnetic valve.

Background

in modern industrial manufacturing, the degree of automation is increasing and the use of automatic control elements is undoubtedly becoming more widespread. The performance parameters of the solenoid valve as a control element in the system are an important link in the control system. The most important performance parameter of the solenoid valve is the response time of the solenoid valve, and the sensitivity is higher as the response time is shorter.

At present, the response time of electromagnetic valves of various manufacturers is different, but the response speed of the electromagnetic valves produced in China is generally slower than that of the electromagnetic valves of foreign brands, and the service life and the stability of the electromagnetic valves are also poor. The response time of the solenoid valve is mainly determined by the sensitivity of the electromagnet of the core component.

Electromagnets of electromagnetic valves used in the current market are all made of soft magnetic materials, and have certain lag in response speed. At present, many researchers do much work in this respect, and are dedicated to reducing the coercivity of electromagnetic materials, and they all achieve certain results, but since their research is based on soft magnetic materials, although the coercivity of materials can be greatly reduced, the coercivity always exists and cannot be completely eliminated. Therefore, the development of a novel zero-coercivity electromagnetic valve material is a subject with great market application prospect.

Under the condition of small size, when the anisotropy energy is reduced to be equivalent to the thermal motion energy, the magnetization direction is not fixed in an easy magnetization direction any more, and the easy magnetization direction is changed irregularly to become a superparamagnetic material. The superparamagnetic material is different from the traditional magnetic material in that the superparamagnetic material has no magnetic hysteresis loop and zero coercive force, so that the change relation of magnetism along with the magnetic field intensity of a magnetization field is a straight line, and no hysteresis exists. It is clear that the problem of hysteresis can be solved very well if the electromagnet material can be used as an electromagnetic valve.

It is seen that improvements and enhancements to the prior art are needed.

Disclosure of Invention

in view of the above-mentioned shortcomings of the prior art, a first object of the present invention is to provide a superparamagnetic electromagnetic composite material, which has the advantages of zero coercivity and no hysteresis loop.

the second objective of the present invention is to provide a method for preparing a superparamagnetic electromagnetic composite material, so as to prepare a superparamagnetic electromagnetic composite material.

The third purpose of the present invention is to provide a high-sensitivity electromagnetic valve, wherein the static iron core and the movable iron core are prepared from the electromagnetic composite material, and the present invention aims to solve the technical problem that the sensitivity cannot be improved due to the hysteresis of the electromagnet in the conventional electromagnetic valve.

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

A superparamagnetic electromagnetic composite material comprises a raw material A and a raw material B, wherein the raw material A is nano ferroferric oxide, and the raw material B is epoxy resin or polytetrafluoroethylene; according to the mass percentage, the nano ferroferric oxide accounts for 10-70%.

In the superparamagnetic electromagnetic composite material, the nano ferroferric oxide accounts for 50 percent by mass.

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

A method of making an electromagnetic composite material as described above, the method comprising the steps of:

S100: weighing a raw material A and a raw material B;

S200: respectively adding the weighed raw material A and the weighed raw material B into a ball mill for ball milling and mixing;

s300: after ball milling and mixing, putting the uniformly mixed raw materials into a die, and performing compression molding to obtain a green body;

s400: and carrying out a curing reaction on the obtained green body to obtain the superparamagnetic electromagnetic composite material.

In the preparation method of the electromagnetic composite material, the ratio of the ball milling medium added into the ball mill to the total amount of the raw material A and the raw material B is 1: 1.

in the preparation method of the electromagnetic composite material, the ball milling medium is zirconia grinding balls.

In the preparation method of the electromagnetic composite material, the rotating speed of the ball mill is 40-50 r/min, and the ball milling time is 10-20 h.

In the preparation method of the electromagnetic composite material, the particle size of the raw material A is 10-30 nm.

In the preparation method of the electromagnetic composite material, the green body forming pressure is 5-25 MPa.

In the preparation method of the electromagnetic composite material, the curing reaction temperature is 180-360 ℃, and the curing time is 90-120 min.

In order to achieve the third object, the invention adopts the following technical scheme:

A high-sensitivity electromagnetic valve is provided with a static iron core and a movable iron core which are made of the electromagnetic composite material.

Has the advantages that:

the invention takes nano ferroferric oxide and epoxy resin or nano ferroferric oxide and polytetrafluoroethylene as raw materials, and compounds the raw materials under certain conditions to prepare a novel superparamagnetic electromagnetic composite material with zero coercive force, which is used for replacing the traditional metal soft magnet.

The raw material A and the raw material B are uniformly mixed through a ball mill, then the mixture is placed into a mould to be pressed and formed to obtain a green body, and then the green body is solidified at a certain temperature to obtain the electromagnetic composite material with a certain shape. In addition, the electromagnetic composite material has good cutting performance, can be made into any shape according to the requirement, has simple process, is easy for large-scale production and has high practical value.

And finally, preparing a static iron core and a movable iron core of the electromagnetic valve by using the electromagnetic composite material so as to improve the sensitivity of the electromagnetic valve.

Drawings

fig. 1 is a flow chart of a method for preparing an electromagnetic composite material according to the present invention.

Detailed Description

the invention provides a superparamagnetic electromagnetic composite material and a preparation method thereof, and also provides a high-sensitivity electromagnetic valve, so that the purpose, the technical scheme and the effect of the invention are clearer and clearer, and the invention is further described in detail by referring to the attached drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The invention provides a superparamagnetic electromagnetic composite material, which comprises a raw material A and a raw material B, wherein the raw material A is nano ferroferric oxide, and the raw material B is epoxy resin or polytetrafluoroethylene; according to the mass percentage, the nano ferroferric oxide accounts for 10-70%. For example, the nano ferroferric oxide accounts for 10%, 30%, 50% and 70% by mass; more preferably, the nano ferroferric oxide is 50%.

In addition, as shown in fig. 1, the present invention provides a method for preparing the electromagnetic composite material, which comprises the following steps:

S100: weighing a raw material A and a raw material B;

S200: respectively adding the weighed raw material A and the weighed raw material B into a ball mill for ball milling and mixing;

s300: after ball milling and mixing, putting the uniformly mixed raw materials into a die, and performing compression molding to obtain a green body;

S400: and carrying out a curing reaction on the obtained green body to obtain the superparamagnetic electromagnetic composite material.

Wherein the ratio of the ball milling medium added into the ball mill to the total amount of the raw material A and the raw material B is 1: 1. preferably, the ball milling medium is zirconia balls, that is, the ratio of zirconia to raw materials is 1:1, and the raw materials comprise a raw material A and a raw material B.

The rotating speed of the ball mill is 40-50 r/min, such as 40r/min, 45r/min and 50r/min, and the ball milling time is 10-20 h, such as 10h, 15h and 20 h. More preferably, the rotating speed is 45r/min and the time is 15 h.

The particle size of the raw material A is 10-30 nm.

the green body forming pressure is 5-25 MPa, such as 5MPa, 15MPa, 20MPa and 25 MPa.

The temperature of the curing reaction is 180-360 ℃, such as 180 ℃, 270 ℃ and 360 ℃; the curing time is 90-120 min, such as 90min, 100min and 120 min.

Firstly, preparing nano ferroferric oxide powder. Weighing a proper amount of anhydrous ferric chloride according to a formula, dissolving ferrous sulfate heptahydrate and polyacrylic acid in water, adjusting the pH value to 9 by using ammonia water to obtain a black colloidal solution, supplementing a proper amount of polyacrylic acid solution, performing ultrafiltration for a period of time at 50 ℃, performing ultrafiltration concentration for 5 times in a Millipore ultrafiltration device (the aperture of an ultrafiltration membrane is 10KD), removing impurities, dispersing in water, and performing vacuum drying at 60 ℃ for 12 hours to obtain black nano Fe₃O₄The particle size of the powder is distributed in a range of 10-30 nm.