CN108242501A - magnetostrictive device and preparation method thereof - Google Patents

Abstract

Disclosed is a magnetostrictive device, which includes a magnetostrictive band core, characterized in that the magnetostrictive band core has a columnar structure, the opposite section has a spiral loop, and the outer circumferential direction of the band core is wound to generate a magnetic field. Induction coil; the magnetostrictive tape core is formed by winding a flat strip, and the lamination coefficient N is 75% to 85%. The magnetostrictive device can reduce the eddy current loss of the magnetostrictive material at high frequency, improve the actuation precision of the magnetostrictive material, and broaden the application field of the material; at the same time, it also improves the utilization efficiency of the quenched magnetostrictive material.

Description

Magnetostrictive device and its preparation method

technical field

The invention relates to a magnetostrictive device and a preparation method thereof, belonging to the field of magnetic material devices.

Background technique

Fe-Ga alloy is a new type of magnetostrictive material. Compared with traditional Terfenol-D, its biggest feature is that it has a lower saturation magnetic field and higher mechanical strength, and the saturation field is as low as 8-17kA/m , about 1/10 of Terfenol-D, high magnetic field sensitivity. In some applications, there is no need to use complex prestressed structures, and the device structure design is relatively simple. Fe-Ga alloy is a metal solid solution with high strength, low brittleness, high tensile strength (500MPa) and ductility, especially suitable for harsh conditions with strong vibration, impact, heavy load and strong corrosion. In addition, the alloy has high magnetic permeability, high Curie temperature, good temperature characteristics, and can be used in a wide temperature range, so it has good application prospects in sensors and actuators .

The saturation magnetostriction coefficient of Fe-Ga alloy prepared by traditional directional solidification method is only 200-300ppm, which is much smaller than 2000ppm of Terfenol-D. In addition, due to the high electrical conductivity of the Fe-Ga alloy, large eddy current losses will occur when the alloy bulk material is used under high frequency conditions. These limit the scope of application, so improving the magnetostrictive properties of Fe-Ga alloy and reducing the eddy current loss during its service has become one of the key factors for its application.

In view of the above problems, due to the good ductility of FeGa alloys, in practical applications, Fe-Ga alloys can be made into thin nanocrystalline strips by rapid quenching or rolling. In this way, the eddy current loss of the material at high frequency can be greatly reduced, and the application range of the material can be expanded.

For example, Chinese patent application CN103320682 A proposes to prepare Fe _100-xy Ga _x M _y material by melt quenching method, and to obtain a quenched strip by using copper crucible method. Chinese patent application CN103556045 A proposes a pseudo-binary material of FeGa and TbDyFe, and adopts the principle of anisotropy compensation to obtain a rapidly quenched FeGa material with large magnetic strain, low driving field and high mechanical properties. Chinese patent application CN105177227 A proposes to rapidly quench FeGa materials.

However, in practical applications, how to apply thin strip-shaped FeGa materials, make full use of its large magnetostrictive properties, and improve its high-frequency magnetostrictive properties and precision actuation stability is still a relatively difficult problem that people face. Big technical problem.

Contents of the invention

In order to solve the above technical problems, the inventor proposes a novel magnetostrictive bulk device and a preparation method thereof. The device has high magnetostriction coefficient and low eddy current loss.

In order to achieve the above object, on the one hand, the present invention intends to adopt the following technical solutions: a magnetostrictive device, the device includes a magnetostrictive core, characterized in that the magnetostrictive core is a columnar structure, relatively The cross-section has a spiral loop, and an induction coil that generates a magnetic field is wound around the outer circumference of the core; the magnetostrictive core is wound from a flat strip, and the lamination coefficient N is 75% to 85%.

In actual use, the induction coil is energized to generate a magnetic field, and the magnetostrictive core inside the coil generates magnetostriction under the action of the magnetic field.

The traditional production method is the lamination method, that is, the magnetostrictive thin sheets prepared by the quick quenching method or the rolling method are stacked together, and the material utilization rate of these methods is low. More importantly, when a magnetic field is applied, it is difficult to ensure that the magnetic field is evenly distributed on the material, so that the laminations are not uniformly affected by the magnetic field, and the expansion and contraction are inconsistent, making it difficult to achieve precise actuation control.

In the present invention, since the coil is ring-shaped, the magnetic field inside the ring is uniformly distributed. In this case, the magnetostrictive tape core is prepared by the winding method, which can achieve uniform magnetic field distribution and uniform expansion and contraction of each spiral loop, thereby achieving more precise control.

Therefore, the magnetostrictive tape core is formed by winding a flat tape. In the present invention, the preferred flat strip preparation method is the rapid quenching method, which is obtained by spreading the molten alloy steel on a rotating roller for rapid cooling. By this method, the segregation of the alloy components can not only be effectively suppressed, but also the It is conducive to the precise control of the width and thickness of the magnetostrictive strip, so as to achieve high consistency of the strip core after winding.

The magnetostrictive tape core prepared by the quick quenching method is wound to form a columnar structure, and the opposite section has a helical loop.

According to the aforementioned magnetostrictive device, wherein, the lamination coefficient N is the effective area coefficient of the band core, by measuring the inner diameter D1 of the band core, the outer diameter D2, the number n of spiral loops, and the thickness d, calculated by the following formula :

The higher the lamination factor, the larger the effective area of the core. Advantageously, the lamination factor of the spiral loop is 75-85%. The lamination coefficient is lower than 75%, indicating that the distribution of the spiral loop in the belt core is uneven, which affects the final precision actuation effect. The lamination coefficient is too high, on the one hand, it will bring more trouble to the manufacturing, on the other hand, it will also affect the high frequency use performance.

According to the aforementioned magnetostrictive device, wherein, the main component of the magnetostrictive core is Fe _100-xy Ga _x M _y , and M is one of Al, Ni, Co, Si, B, La, Y, Ce or more, wherein 5≤x≤25, 0≤y≤10, all are mass ratios.

The main consideration of using FeGa material is that compared with the traditional Terfenol-D, its biggest feature is its lower saturation magnetic field and higher mechanical strength. The saturation field is only 8-17kA/m, which is about 1 of Terfenol-D. /10, high magnetic field sensitivity. In some applications, there is no need to use complex prestressed structures, and the device structure design is relatively simple. At the same time, Fe-Ga alloy is a metal solid solution with high strength and low brittleness. It also has high tensile strength (500MPa) and ductility, especially It is suitable for harsh conditions with strong vibration, impact, heavy load and strong corrosion.

According to the aforementioned magnetostrictive device, wherein, the main component of the magnetostrictive core is prepared by a rapid quenching method. The FeGa material prepared by the rapid quenching method is conducive to exerting its advantages in mechanical properties, and the thickness of the prepared strip is only about 1/10 of the rolled strip, which is more conducive to exerting its performance under high frequency.

In the FeGa composition of the present invention, 5≤x≤25 and 0≤y≤10 are mass ratios. Within this composition range, it is beneficial to obtain a single A2 phase alloy and avoid the appearance of ordered phases such as DO3, DO19, and L12. Single phase is beneficial to obtain higher magnetostrictive performance. The addition of a certain amount of the third component M can not only maintain the basic structural properties of Fe-Ga alloys, but also improve the magnetostrictive properties, Curie temperature, and machinability of the alloys. Among them, the addition of Al and Ni can improve the material properties. Excellent machinability, improve the ductility of the fast-quenched flat strip, and improve the flatness of the strip; the addition of Co can improve its temperature and temperature resistance; the addition of Si and B can improve the stability of rapid quenching and reduce the surface of the strip. The roughness is conducive to the formation of a single A2 structure; the addition of La, Y, and Ce can improve its soft magnetic properties and improve the magnetic stability of the material at high frequencies. The content of M is in the range of 0-10wt.%, wherein y=0 means a single FeGa material, and the content of M higher than 10wt.% will cause the decrease of the magnetostrictive performance obviously.

According to the aforementioned magnetostrictive device, wherein, the thickness of the flat strip is 50-150 μm, and the width is greater than 10 mm.

Advantageously, in the magnetostrictive tape core, the flat tape has a thickness of 50-150 μm and a width greater than 10 mm. The thickness within this range is conducive to improving the high-frequency performance of the magnetostrictive device, but the thickness of the flat strip less than 50 μm will cause difficulties in preparation, the flatness of the flat strip is poor, the lamination coefficient is low, and the thickness greater than 150 μm will be unfavorable. performance at high frequencies. Generally, in order to achieve the use effect of the device, the strip width of the present invention is greater than 10mm, and can be appropriately cut according to the specific use size.

According to the aforementioned magnetostrictive device, an insulating adhesive is filled between the helical loops of the magnetostrictive core.

The existence of the insulating binder further reduces the eddy current loss of the magnetostrictive device at high frequencies, reduces the heating of the device, and improves the application stability and precision of the device.

According to the aforementioned magnetostrictive device, wherein the insulating adhesive is selected from epoxy resin.

According to the aforementioned magnetostrictive device, wherein, in order to further improve the actuation precision of the magnetostrictive device, the magnetic field in the device needs to be evenly distributed. Advantageously, a soft magnetic material is further added to the core of the band core to achieve the purpose of forming a magnetic circuit .

According to the aforementioned magnetostrictive device, wherein, the soft magnetic material includes FeNi powder core, FeSiAl powder core, FeNiMo powder core, iron powder core, ferrite powder core.

On the other hand, the present invention also provides a method for preparing the aforementioned magnetostrictive device of the present invention, comprising the steps of:

(1) Flat strip preparation: the molten alloy melt is sprayed onto the rotating roller by induction spray casting, and the flat strip is prepared by rapid cooling;

(2) winding: extruding and winding the flat strip to form a winding body, that is, a tape core, and the tape core is a spiral loop;

(3) Coil preparation: winding an induction coil outside the core to obtain a magnetostrictive device.

According to the aforementioned method, wherein, after the step (2), a dipping process is included; in this process, the winding body of the tape is immersed in a molten insulating adhesive, so that the adhesive is filled between the helical loops.

According to the aforementioned method, after the step (2), a heat treatment process is included; in this process, the extruded tape winding body is heat treated in the range of 50-300°C.

Compared with the prior art, the present invention has the following advantages:

On the one hand, the magnetostrictive device of the present invention can reduce the eddy current loss of the magnetostrictive material at high frequency, improve the actuation precision of the magnetostrictive material, and broaden the application field of the material; Utilization efficiency of stretchable materials.

Description of drawings

Fig. 1 is a schematic diagram of the magnetostrictive tape core of the present invention.

Detailed ways

The present invention will be further described below in combination with specific embodiments. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content of the present invention, those skilled in the art may make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of the present application.

The following examples will help to understand the present invention, but cannot limit the scope of the present invention.

Example

The magnetostrictive device that the present invention relates to mainly adopts the following methods to obtain:

(1) Flat strip preparation

The flat strip is prepared by spraying the molten alloy solution onto the rotating roller by induction spraying method and rapidly cooling it.

In this preparation process, the tape composition, thickness d (in μm), and width W (in mm) are as shown in Table 1.

The material composition is measured by ICP, and the thickness and width are measured by a spiral micrometer.

(2) Winding

The flat strip is extruded and wound to form a strip winding, which is a helical loop.

After winding, the lamination coefficient of the magnetostrictive band core can be measured. In the present invention, by measuring the inner diameter D1 of the band core, the outer diameter D2, and the number n of spiral loops, the lamination coefficient N can be calculated as:

(3) Coil preparation

An induction coil is wound outside the core to obtain a magnetostrictive device.

The coil is a copper enameled wire, and the number of turns and the diameter of the copper wire are preferably 70-95% of the width of the core.

In order to further improve the high-frequency application characteristics of the magnetostrictive material, the following steps of dipping and heat treatment are added.

Dipping: Dip the winding body of tape into molten insulating adhesive, so that the adhesive is filled between the helical loops.

Heat treatment: heat-treat the rolled body after extrusion in the range of 50-300°C.

The loss P (in W/kg) and the magnetostriction coefficient λ of the final device are also shown in Table 1.

Table 1 Composition and performance of magnetostrictive device

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention are included within the protection scope of the present invention.

Claims (10)

1. a kind of magnetostrictive device, the device includes a magnetostriction belt carcass, which is characterized in that the magnetostriction belt carcass Structure is in the form of a column, there is helical loop with respect to section, the winding of belt carcass outer circle circumferential direction generates the induction coil in magnetic field；The mangneto Flexible belt carcass is by flat strip coil around into lamination coefficient N is 75%~85%；

The lamination coefficient N is the effective area coefficient of belt carcass, by measuring the internal diameter D1 of belt carcass, outer diameter D 2, helical loop piece Number n, thickness d are calculated by following equation：

2. magnetostrictive device according to claim 1, which is characterized in that the magnetostriction belt carcass main component is Fe_100-x-yGa_xM_y, it is one or more in M Al, Ni, Co, Si, B, La, Y, Ce, wherein 5≤x≤25,0≤y≤10 are Mass ratio.

3. magnetostrictive device according to claim 1, which is characterized in that the flat thickness of strip is 50~150 μ M, width are more than 10mm.

4. magnetostrictive device according to claim 1, which is characterized in that the magnetostriction belt carcass main component uses Quick quenching technique is prepared.

5. magnetostrictive device according to claim 1, which is characterized in that the helical loop of the magnetostriction belt carcass it Between be filled with insulating adhesive.

6. magnetostrictive device according to claim 5, which is characterized in that the insulating adhesive includes epoxy resin.

7. magnetostrictive device according to claim 1, which is characterized in that the magnetostriction belt carcass core further increases Add soft magnetic materials.

A kind of 8. method for preparing any one of the claim 1-7 magnetostrictive devices, which is characterized in that including walking as follows Suddenly：

(1) prepared by flat band：The alloy molten solution of melting is ejected on the roller of rotation by sensing spray to cast method, fast quickly cooling But flat band is prepared；

(2) it winds：It squeezes and winds the flat band, form tape wrapping body, that is, belt carcass, the belt carcass is helical loop；

(3) prepared by coil：Induction coil is externally wrapped in belt carcass, obtains magnetostrictive device.

9. according to the method described in claim 8, it is characterized in that, after step (2), including an impregnation process；The process Tape wrapping body is immersed in melting insulating adhesive, makes filling adhesive between helical loop.

10. according to the method described in claim 8, it is characterized in that, after step (2), including a heat treatment procedure；The work Tape wrapping body after extruding is heat-treated by sequence in the range of 50~300 DEG C.