CN111004912B

CN111004912B - Electric pulse processing method for amorphous alloy structure relaxation

Info

Publication number: CN111004912B
Application number: CN201911226536.4A
Authority: CN
Inventors: 姚可夫; 施凌翔
Original assignee: Tsinghua University
Current assignee: Tsinghua University
Priority date: 2019-12-04
Filing date: 2019-12-04
Publication date: 2021-09-10
Anticipated expiration: 2039-12-04
Also published as: CN111004912A

Abstract

The invention belongs to the technical field of structural treatment of amorphous alloys, and particularly relates to a method for carrying out electric pulse treatment on an amorphous alloy. The method comprises the steps of controlling parameters such as pulse form, pulse width, pulse interval, current density and the like of electric pulses, sample temperature during electric pulse treatment and cooling speed of a sample after treatment, so as to realize rapid structural relaxation of the amorphous alloy, and realize structural relaxation regulation and performance regulation of the amorphous alloy. Compared with the traditional isothermal annealing heat treatment process, the method has the advantages of high efficiency, small temperature rise of the amorphous alloy sample, low sample temperature and capability of effectively avoiding the surface oxidation of the amorphous alloy. And the relaxation degree of the amorphous alloy structure can be effectively regulated and controlled, so that the amorphous alloy obtains more excellent structure and performance.

Description

Electric pulse processing method for amorphous alloy structure relaxation

Technical Field

The invention belongs to the technical field of amorphous alloy treatment, and particularly relates to a method for carrying out electric pulse treatment on an amorphous alloy.

Background

Amorphous alloy (also called metallic glass) is a new type of metallic material. Because the atoms are in long-range disordered stacking arrangement, the amorphous alloy has various mechanical, physical and chemical properties superior to those of the same-component crystalline alloy, such as high hardness, high strength, high resistance, corrosion resistance, wear resistance and the like. In addition, compared with the traditional crystalline alloy soft magnetic material, the soft magnetic amorphous alloy has the advantages that the atoms of the amorphous alloy are in disordered arrangement, the amorphous alloy does not have the anisotropic characteristic of crystals, the magnetic permeability is high, the coercive force is low, the resistivity is high, the iron loss is much lower than that of the traditional silicon steel, and the soft magnetic material is excellent in performance. The amorphous alloy has the excellent performance, so that the amorphous alloy has wide application prospects in the fields of energy, electronics, machinery, chemical engineering, military industry and the like.

However, various properties of amorphous alloys tend to be very sensitive to their thermal history: the properties of the amorphous alloy prepared at different cooling speeds, such as toughness, coercive force, magnetic permeability and the like, have obvious differences. Therefore, in the industrial application of amorphous alloy, such as the application of soft magnetic iron-based amorphous alloy, the influence of the thermal history of the alloy and the structural performance are often required to be adjusted by a structural relaxation treatment method.

At present, the main structural relaxation means of amorphous alloy is heat treatment, that is, the amorphous alloy is placed at a certain temperature lower than the crystallization temperature for a certain time and then cooled. However, since the heat transfer efficiency from the heat treatment apparatus to the amorphous alloy is not high, a long heat treatment time is usually required to achieve a good structure relaxation effect. In addition, because of the higher processing temperature, for example, the iron-based amorphous alloy often needs to be heat-treated at more than 300 ℃, and in order to prevent the amorphous alloy from being oxidized, protective gas is generally required to be introduced. This makes the conventional heat treatment process costly and time consuming. Particularly, for some special applications, it is desirable to adjust the relaxation state of the amorphous alloy structure, and in this case, it is often difficult to obtain the desired structure relaxation effect by the conventional isothermal annealing process.

In summary, the conventional isothermal heat treatment annealing method has the above problems, which significantly affect the relaxation treatment effect, production efficiency and production cost of the amorphous alloy structure, and especially for the amorphous alloy products with special requirements, the conventional isothermal heat treatment annealing method is difficult to meet the requirements. Therefore, it is necessary to develop a new structure relaxation method to meet the requirements of realizing rapid structure relaxation of amorphous alloy, and structural performance regulation and engineering application.

Disclosure of Invention

Technical problem to be solved by the invention

Aiming at the problems of the existing amorphous alloy isothermal heat treatment annealing process and the requirement of realizing structure relaxation, the invention provides a method for realizing rapid structure relaxation of amorphous alloy, which realizes rapid structure relaxation of amorphous alloy in a thermal and electric coupling energy input mode by applying pulse current to the amorphous alloy and adjusting the combination of current parameters (such as pulse form, pulse width, pulse interval, current density and the like) and processing time.

Means for solving the technical problem

Aiming at the problems, the invention provides a method for processing amorphous alloy.

According to an embodiment of the present invention, there is provided a method for relaxing a structure of an amorphous alloy, wherein the method for processing the amorphous alloy includes the steps of:

(1) connecting two ends of the amorphous alloy sample with two electrodes or positive and negative electrodes of a pulse power supply respectively;

(2) placing the amorphous alloy sample in media with poor conductivity at different temperatures, and regulating and controlling the temperature of the sample; and/or placing the amorphous alloy sample in different external fields to regulate and control the stress field and the magnetic field born by the sample;

(3) and introducing pulse current, and controlling the pulse form, pulse width, pulse interval and current density of the electric pulse to realize the rapid structural relaxation of the amorphous alloy.

(4) In the electric pulse treatment process, parameters of the pulse form, the pulse width, the pulse interval and the current density of the electric pulse can be kept unchanged, and can also be adjusted in the treatment process or automatically adjusted according to preset parameters.

(5) After pulse current input to the amorphous alloy sample is stopped, the cooling speed (or heating speed) of the sample is regulated by a method of placing the sample in media with different temperatures or contacting the sample with materials at different temperatures, namely, the cooling or heating speed of the sample from the temperature during processing to the subsequent set temperature is regulated.

In one embodiment, the pulse form is an ac pulse or a dc pulse.

In one embodiment, the pulse width is 0.1 to 999000 μ s.

In one embodiment, the pulse interval is 1 to 999000 μ s.

In one embodiment, the current density is 0.1 to 20000A/mm 2.

In one embodiment, the environmental temperature of the sample can be regulated, and the sample temperature during the electric pulse treatment can be regulated by placing the sample in environment media with poor conductivity at different temperatures; meanwhile, the state of the sample can be regulated and controlled, and the state of the sample during the electric pulse treatment can be regulated and controlled by placing the sample in different external fields.

In one embodiment, the amorphous alloy may be subjected to intermittent structural relaxation, wherein the intermittent electric pulse combination treatment may be performed at different time intervals and with different electric treatment parameters during the electric treatment of the amorphous alloy sample.

According to a second aspect of the invention, the method is applied to the treatment of iron-based, cobalt-based and nickel-based amorphous alloy strips.

According to a third aspect of the present invention, a continuous rapid structure method of amorphous alloy is provided, which adopts the above method, wherein, the two electrodes or positive and negative electrodes of the pulse power supply in step (1) are conductive rollers, the amorphous alloy strip is contacted with 2 conductive rollers (or called rollers), so as to introduce current into the moving amorphous strip, and the driving wheel is used for driving the amorphous strip (or plate) to move, so as to implement the relaxation treatment of the continuous structure of the amorphous alloy strip.

The invention has the advantages of

The method has high structural relaxation efficiency and short required time, and when the same structural relaxation effect is achieved, the sample temperature is far lower than the traditional isothermal annealing temperature, so that the surface oxidation of the amorphous alloy can be effectively avoided, and the method can regulate the structural relaxation degree of the amorphous alloy sample. Because the structure relaxation is related to the mechanical, physical and chemical properties of the amorphous alloy, the method can realize the performance regulation of the amorphous alloy so as to meet the use performance requirements of the amorphous alloy.

Further features of the present invention will become apparent from the following description of exemplary embodiments.

Drawings

Fig. 1 is a graph of the coercivity and relative strain to break of a Fe78B13Si9 amorphous alloy ribbon after being processed by the electric pulse processing parameters described in examples 1, 2 and 4-9.

FIG. 2 is a graph of the coercivity and relative strain to break of Fe78B13Si9 amorphous alloy ribbon after annealing parameters described in comparative examples 1, 2 and 3-7.

FIG. 3 is a coercivity map of Fe78B13Si9 amorphous alloy ribbons after being subjected to the electrical pulse treatment parameters described in examples 2, 3 and 10-15 and the annealing parameters described in comparative examples 8-14.

Fig. 4 is a graph of relative fracture strain of Fe78B13Si9 amorphous alloy ribbon after being processed by the electric pulse processing parameters described in examples 2, 3 and 10-15, wherein the small graph is a graph of bending of the ribbon after being processed by the electric pulse parameters described in example 3.

Detailed Description

The following describes an embodiment of the present disclosure in detail, but the present disclosure is not limited thereto.

The invention discloses a structural relaxation method of amorphous alloy, which realizes structural relaxation and performance regulation. Specific embodiments are as follows.

The specific embodiment of the invention is as follows: connecting an amorphous alloy sample with two poles of an output end of a pulse power supply, and controlling parameters such as pulse form, pulse width, pulse interval, current density and the like of electric pulses, sample temperature during electric pulse treatment and cooling speed after sample treatment, thereby realizing structural relaxation and performance regulation of the amorphous alloy. The surface oxidation of the amorphous alloy is effectively avoided, and the relaxation degree of the amorphous alloy structure is effectively adjusted and controlled, so that the amorphous alloy obtains more excellent service performance.

In order to make the content, technical scheme and advantages of the present invention more comprehensible, the present invention is further explained with reference to the accompanying drawings and specific embodiments. It should be noted that the specific embodiments described herein are only for illustrating the present invention and do not limit the present invention.

According to one embodiment of the invention, the rapid relaxation processing method for the amorphous alloy adopts the form of electric pulses for enabling the amorphous alloy to reach different relaxation states.

In this embodiment, by optimizing parameters, commercial soft magnetic amorphous alloy ribbon (1K101, also called Metglas 2605-SA, with a composition of about Fe78B13Si9) widely used at present is subjected to electric pulse treatment, and by adjusting and controlling process parameters, the relaxation of the amorphous alloy structure is rapidly realized, and the performance of the iron-based amorphous alloy ribbon is adjusted and controlled. And preparing the soft magnetic iron-based amorphous alloy strip with the same or better soft magnetic performance or other performances than isothermal heat treatment annealing treatment. However, the amorphous alloy to which the method of the present invention is applicable is not limited thereto: in the aspect of components, the method is suitable for amorphous alloys of various systems and various components; in the aspect of sample shape, samples in various shapes can be processed by changing a clamping device for connecting two output poles of a pulse power supply and amorphous alloy; in the aspect of a clamping mode, the clamping device can be changed into a conductive roller, so that the continuous processing of the amorphous sample is realized; the treatment medium used can be either air or another medium.

TABLE 1 coercivity and relative strain to failure of Fe78B13Si9 amorphous alloy ribbons treated under the parameters described in examples 1-3 and comparative examples 1-2

Example 1:

in this embodiment, the method specifically includes the following steps:

(1) respectively connecting two ends of the Fe78B13Si9 amorphous alloy strip with two poles of a pulse power supply;

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulses with the pulse width of 25 mus and the pulse interval of 250 mus, wherein the current density amplitude of the electric pulse treatment is about 833A/mm2, and the pulse current treatment time is about 60 s;

(4) the input of the pulse current was stopped, and the sample was allowed to cool naturally in air at room temperature.

After the structure relaxation treatment was performed, the structure of the sample was tested using an X-ray diffractometer. The coercive force Hc of the sample was measured using a soft magnetic DC testing apparatus (maximum applied magnetic field of 800A/m). Bending the processed strip sample into a U shape, placing the U-shaped strip sample in two flat plates, enabling the two flat plates to gradually approach at a certain speed until the sample is broken or permanently deformed, and recording the distance between the two flat plates when the sample is broken as 2 gamma. Defining the relative breaking strain as: λ ═ t/(2 γ -t), where t is the thickness of the strip sample. If the sample does not break after permanent deformation, λ is 1. The larger the lambda value, the higher the toughness of the sample.

The X-ray diffraction test result shows that the treated sample still keeps an amorphous structure. The measured magnetic and mechanical properties are shown in table 1. Wherein: the coercive force Hc was 3.8A/m, B800 was 1.35T, and the relative strain at break λ was 1.0. No obvious oxidation trace on the surface of the sample.

Example 2:

in this embodiment, the method specifically includes the following steps:

(1) connecting two ends of the Fe78B13Si9 amorphous alloy strip with the positive electrode and the negative electrode of a pulse power supply respectively;

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulses, wherein the pulse width is 40 mus, the pulse interval is 250 mus, the current density amplitude of the electric pulse treatment is about 833A/mm2, and the pulse current treatment time is about 60 s;

The X-ray diffraction test result shows that the treated sample still keeps an amorphous structure. The measured magnetic and mechanical properties are shown in table 1. Wherein: coercive force Hc is 1.2A/m, B800 is 1.36T, and relative breaking strain lambda is 0.033. The surface of the sample has no oxidation traces.

Example 3:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulses, wherein the pulse width is 40 mus, the pulse interval is 250 mus, the current density amplitude of the electric pulse treatment is about 833A/mm2, and the pulse current treatment time is about 5 s;

The X-ray diffraction test result shows that the treated sample still keeps an amorphous structure. The measured magnetic and mechanical properties are shown in table 1. Wherein: coercive force Hc is 1.4A/m, B800 is 1.44T, and relative breaking strain lambda is 1.0. The surface of the sample has no oxidation traces.

Example 4:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulses with the pulse width of 20 mus and the pulse interval of 250 mus, wherein the current density amplitude of the electric pulse treatment is about 833A/mm2, and the pulse current treatment time is about 60 s;

The X-ray diffraction test result shows that the treated sample still keeps an amorphous structure. The coercivity Hc of the amorphous ribbon was measured to be 4.8A/m, B800 to be 1.28T, and the relative strain at break λ to be 1.0. The surface of the sample has no oxidation traces.

Example 5:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulses with the pulse width of 30 mus and the pulse interval of 250 mus, wherein the current density amplitude of the electric pulses treatment is about 833A/mm2, and the pulse current treatment time is about 60 s;

The X-ray diffraction test result shows that the treated sample still keeps an amorphous structure. The coercive force Hc of the amorphous strip measured was 2.4A/m, B800 was 1.38T, and the relative strain at break λ was 0.054. The surface of the sample has no oxidation traces.

Example 6:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulses, wherein the pulse width is 35 mu s, the pulse interval is 250 mu s, the current density amplitude of the electric pulse treatment is about 833A/mm2, and the pulse current treatment time is about 60 s;

The X-ray diffraction test result shows that the treated sample still keeps an amorphous structure. The coercivity Hc of the treated tape was measured to be 2.4A/m, B800 to be 1.34T, and the relative strain at break λ to be 0.039. The surface of the sample has no oxidation traces.

Example 7:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulses, wherein the pulse width is 45 mus, the pulse interval is 250 mus, the current density amplitude of the electric pulse treatment is about 833A/mm2, and the pulse current treatment time is about 60 s;

The coercive force Hc of the sample was measured using a soft magnetic DC testing apparatus (maximum applied magnetic field of 800A/m). Bending the processed strip sample into a U shape, placing the U-shaped strip sample in two flat plates, enabling the two flat plates to gradually approach at a certain speed until the sample is broken or permanently deformed, and recording the distance between the two flat plates when the sample is broken as 2 gamma. Defining the relative breaking strain as: λ ═ t/(2 γ -t), where t is the thickness of the strip sample. If the sample does not break after permanent deformation, λ is 1. The larger the lambda value, the higher the toughness of the sample.

The coercivity Hc of the treated tape was 11.8A/m, B800 1.25T, and the relative strain at break λ was 0.024.

Example 8:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulses with the pulse width of 50 mus and the pulse interval of 250 mus, wherein the current density amplitude of the electric pulse treatment is about 833A/mm2, and the pulse current treatment time is about 60 s;

The coercivity Hc of the treated tape was 26.4A/m, B800 0.64T, and the relative strain at break λ was 0.016.

Example 9:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulses, wherein the pulse width is 40 mus, the pulse interval is 250 mus, the current density amplitude of the electric pulse treatment is about 833A/mm2, and the pulse current treatment time is about 10 s;

The X-ray diffraction test result shows that the treated sample still keeps an amorphous structure. The coercivity Hc of the treated tape was 1.6A/m, B800 1.39T, and the relative strain at break was 0.048.

Example 10:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulses, wherein the pulse width is 40 mus, the pulse interval is 250 mus, the current density amplitude of the electric pulse treatment is about 833A/mm2, and the pulse current treatment time is about 20 s;

The X-ray diffraction test result shows that the treated sample still keeps an amorphous structure. The coercivity Hc of the treated tape was 1.9A/m, B800 1.30T, and the relative strain at break λ was 0.032.

Example 11:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulses, wherein the pulse width is 40 mus, the pulse interval is 250 mus, the current density amplitude of the electric pulse treatment is about 833A/mm2, and the pulse current treatment time is about 30 s;

The X-ray diffraction test result shows that the treated sample still keeps an amorphous structure. The coercivity Hc of the treated tape was 1.6A/m, B800 1.27T, and the relative strain at break λ was 0.033.

Example 12:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulses, wherein the pulse width is 40 mus, the pulse interval is 250 mus, the current density amplitude of the electric pulse treatment is about 833A/mm2, and the pulse current treatment time is about 40 s;

The X-ray diffraction test result shows that the treated sample still keeps an amorphous structure. The coercivity Hc of the treated tape was 1.5A/m, B800 1.36T, and the relative strain at break λ was 0.034.

Example 13:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulses, wherein the pulse width is 40 mus, the pulse interval is 250 mus, the current density amplitude of the electric pulse treatment is about 833A/mm2, and the pulse current treatment time is about 50 s;

The X-ray diffraction test result shows that the treated sample still keeps an amorphous structure. The coercive force Hc of the treated tape was 1.4A/m, B800 1.32T, and the relative strain at break λ was 0.028.

Example 14:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulses with the pulse width of 50 mus, and connecting negative pulse current after positive pulse, wherein the pulse interval is 1000 mus, the current density amplitude of electric pulse treatment is about 833A/mm2, and the pulse current treatment time is about 60 s;

The coercive force Hc of the sample was measured using a soft magnetic DC testing apparatus (maximum applied magnetic field of 800A/m).

The coercivity Hc of the treated tape was measured to be 4.8A/m and B800 to be 1.32T.

Example 15:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulses with the pulse width of 80 mus, and connecting negative pulse current after positive pulse, wherein the pulse interval is 1000 mus, the current density amplitude of electric pulse treatment is about 833A/mm2, and the pulse current treatment time is about 60 s;

The coercivity Hc of the treated tape was measured to be 4.4A/m and B800 to be 1.36T.

Example 16:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulses with the pulse width of 110 mus, connecting negative pulse current after positive pulse, wherein the pulse interval is 1000 mus, the current density amplitude of electric pulse processing is about 833A/mm2, and the pulse current processing time is about 60 s;

The coercivity Hc of the treated tape was 1.5A/m and B800 was 1.50T.

Example 17:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulse with the pulse width of 140 mus, connecting negative pulse current after positive pulse, wherein the pulse interval is 1000 mus, the current density amplitude of electric pulse treatment is about 1660A/mm2, and the pulse current treatment time is about 60 s;

The coercive force Hc of the sample was measured using a soft magnetic DC testing apparatus (maximum applied magnetic field of 800A/m). The coercivity Hc of the treated tape was measured to be 1.2A/m and B800 to be 1.49T.

Example 18:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulse with the pulse width of 170 mus, connecting negative pulse current after positive pulse, the pulse interval is 1000 mus, the current density amplitude of electric pulse treatment is about 1660A/mm2, and the pulse current treatment time is about 60 s;

The coercivity Hc of the treated tape was measured to be 3.6A/m and B800 to be 1.48T.

Example 19:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulse with the pulse width of 200 mus, connecting negative pulse current after positive pulse, the pulse interval is 1000 mus, the current density amplitude of electric pulse processing is about 1660A/mm2, and the pulse current processing time is about 60 s;

The coercivity Hc of the treated tape was measured to be 12.8A/m and B800 to be 0.27T.

Example 20:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulse with the pulse width of 200 mus, connecting negative pulse current after positive pulse, wherein the pulse interval is 0.999s, the current density amplitude of electric pulse treatment is about 16.7A/mm2, and the pulse current treatment time is about 60 s;

The coercivity Hc of the treated tape was measured to be 5.1A/m and B800 to be 1.33T.

Example 21:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current pulse with the pulse width of 300 mus, connecting negative pulse current after positive pulse, wherein the pulse interval is 0.999s, the current density amplitude of the electric pulse treatment is about 16.7A/mm2, and the pulse current treatment time is about 60 s;

The coercivity Hc of the treated tape was measured to be 5.2A/m and B800 to be 1.34T.

Example 22:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulse with the pulse width of 500 mus, connecting negative pulse current after positive pulse, wherein the pulse interval is 0.999s, the current density amplitude of electric pulse treatment is about 16.7A/mm2, and the pulse current treatment time is about 60 s;

The coercivity Hc of the treated tape was measured to be 4.8A/m and B800 to be 1.34T.

Example 23:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulse with the pulse width of 1000 mus, connecting negative pulse current after positive pulse, wherein the pulse interval is 0.999s, the current density amplitude of electric pulse treatment is about 16.7A/mm2, and the pulse current treatment time is about 60 s;

The X-ray diffraction test result shows that the treated sample still keeps an amorphous structure. The coercivity Hc of the treated tape was measured to be 5.1A/m and B800 to be 1.33T.

Example 24:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulse with the pulse width of 2000 mus, connecting negative pulse current after positive pulse, wherein the pulse interval is 0.999s, the current density amplitude of electric pulse treatment is about 16.7A/mm2, and the pulse current treatment time is about 60 s;

The coercivity Hc of the treated tape was measured to be 5.0A/m and B800 to be 1.33T.

Example 25:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulse with the pulse width of 500000 mu s, and after positive pulse, connecting negative pulse current with the pulse interval of 0.999s, wherein the current density amplitude of electric pulse treatment is about 16.7A/mm2, and the pulse current treatment time is about 60 s;

Example 26:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulse with the pulse width of 999000 mus, connecting negative pulse current after positive pulse, wherein the pulse interval is 0.999s, the current density amplitude of electric pulse treatment is about 16.7A/mm2, and the pulse current treatment time is about 60 s;

The coercive force Hc of the sample was measured using a soft magnetic DC testing apparatus (maximum applied magnetic field of 800A/m). The coercivity Hc of the treated tape was measured to be 5.0A/m and B800 to be 1.33T.

Example 27:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulse with the pulse width of 999000 mus, connecting negative pulse current after positive pulse, wherein the pulse interval is 0.999s, the current density amplitude of electric pulse treatment is about 33.3A/mm2, and the pulse current treatment time is about 60 s;

Example 28:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulse with the pulse width of 999000 mus, connecting negative pulse current after positive pulse, wherein the pulse interval is 0.999s, the current density amplitude of electric pulse treatment is about 50.0A/mm2, and the pulse current treatment time is about 60 s;

The coercive force Hc of the sample was measured using a soft magnetic DC testing apparatus (maximum applied magnetic field of 800A/m). The coercivity Hc of the treated tape was measured to be 166.9A/m and B800 to be 0.32T.

Example 29:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulse with the pulse width of 40 mus, connecting negative pulse current after positive pulse, wherein the pulse interval is 250 mus, the current density amplitude of electric pulse treatment is about 1667A/mm2, and the pulse current treatment time is about 60 s;

The coercivity Hc of the treated tape was measured to be 0.9A/m and B800 to be 1.50T.

Example 30:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulses with the pulse width of 25 mus and the pulse interval of 250 mus, wherein the current density amplitude of the electric pulse treatment is about 833A/mm2, and the pulse current treatment time is about 40 s; the electric pulse treatment was then stopped and the sample cooled to room temperature. Half an hour later, electric pulse treatment is carried out again: the pulse width is 40 mus, the pulse interval is 250 mus, the current density amplitude of the electric pulse treatment is about 833A/mm2, and the pulse current treatment time is about 40 s;

Measuring the coercive force Hc of the strip after the first treatment, wherein the coercive force Hc is 3.1A/m, and the coercive force B800 is 1.50T; after the treatment, the coercive force Hc of the strip was 0.8A/m, and B800 was 1.53T.

Example 31:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulse with the pulse width of 40 mus, connecting negative pulse current after positive pulse, wherein the pulse interval is 250 mus, the current density amplitude of electric pulse treatment is about 1667A/mm2, and the pulse current treatment time is about 40 s;

The coercivity Hc of the treated tape was measured to be 0.9A/m and B800 to be 1.46T.

Example 32:

in this embodiment, the method specifically includes the following steps:

(2) placing the sample in air at room temperature;

(3) introducing alternating current electric pulses, wherein the pulse width is 45 mus, the pulse interval is 250 mus, the current density amplitude of the electric pulse treatment is about 833A/mm2, and the pulse current treatment time is about 5 s; the electric pulse treatment was then stopped and the sample cooled to room temperature. Half an hour later, electric pulse treatment is carried out again: the pulse width is 20 mus, the pulse interval is 250 mus, the current density amplitude of the electric pulse treatment is about 833A/mm2, and the pulse current treatment time is about 60 s;

Measuring the coercive force Hc of the strip after the first treatment to be 1.6A/m, and B800 to be 1.48T; after the treatment, the coercive force Hc of the strip is 1.4A/m, and B800 is 1.48T.

To illustrate the effects of the present invention, the inventors provide the following comparative tests of conventional heat treatment:

(1) placing the Fe78B13Si9 amorphous alloy strip into a quartz tube, vacuumizing, introducing high-purity argon, and sealing to prevent oxidation;

(2) putting the quartz tube into an annealing furnace heated to 340-520 ℃, and preserving heat for 5-600 s;

(3) taking out the quartz tube, and putting the quartz tube into water at room temperature for quenching.

After the isothermal annealing treatment was performed, the structure of the sample was tested using an X-ray diffractometer. The coercive force Hc of the sample was measured using a soft magnetic DC testing apparatus (maximum applied magnetic field of 800A/m). Bending the processed strip sample into a U shape, placing the U-shaped strip sample in two flat plates, enabling the two flat plates to gradually approach at a certain speed until the sample is broken or permanently deformed, and recording the distance between the two flat plates when the sample is broken as 2 gamma. Defining the relative breaking strain as: λ ═ t/(2 γ -t), where t is the thickness of the strip sample. If the sample does not break after permanent deformation, λ is 1. The larger the lambda value, the higher the toughness of the sample.

The X-ray diffraction test result shows that the sample still keeps an amorphous structure after the isothermal annealing treatment at 430 ℃. As shown in FIG. 2, the coercivity of the Fe78B13Si9 amorphous alloy ribbon after annealing reached the lowest value (1.1A/m), indicating that 430 ℃ was the optimal annealing temperature. Comparative examples are as follows.

Comparative example 1:

in this comparative example, the specific procedure was as follows:

(2) putting the quartz tube into an annealing furnace heated to 340 ℃, and preserving heat for 600 s;

After the annealing treatment was performed, the structure of the sample was tested using an X-ray diffractometer. The coercive force Hc of the sample was measured using a soft magnetic DC testing apparatus (maximum applied magnetic field of 800A/m). Bending the processed strip sample into a U shape, placing the U-shaped strip sample in two flat plates, enabling the two flat plates to gradually approach at a certain speed until the sample is broken or permanently deformed, and recording the distance between the two flat plates when the sample is broken as 2 gamma. Defining the relative breaking strain as: λ ═ t/(2 γ -t), where t is the thickness of the strip sample. If the sample does not break after permanent deformation, λ is 1. The larger the lambda value, the higher the toughness of the sample.

The X-ray diffraction test result shows that the sample still keeps an amorphous structure after the annealing treatment. The coercive force Hc of the treated tape was 3.7A/m, B800 was 1.43T, and the relative strain at break λ was 0.014. The measured magnetic and mechanical properties are shown in table 1.

Comparative example 2:

in this comparative example, the specific procedure was as follows:

(2) putting the quartz tube into an annealing furnace heated to 430 ℃, and preserving heat for 600 s;

The X-ray diffraction test result shows that the sample still keeps an amorphous structure after the annealing treatment. The coercive force Hc of the ribbon after the annealing treatment was 1.1A/m, B800 was 1.49T, and the relative strain at break λ was 0.034. The measured magnetic and mechanical properties are shown in table 1.

Comparative example 3:

in this comparative example, the specific procedure was as follows:

(2) putting the quartz tube into an annealing furnace heated to 370 ℃, and preserving heat for 600 s;

The X-ray diffraction test result shows that the sample still keeps an amorphous structure after the annealing treatment. The coercivity Hc of the annealed ribbon was measured to be 2.8A/m, B800 to be 1.51T, and the relative strain at break λ to be 0.035.

Comparative example 4:

in this comparative example, the specific procedure was as follows:

(2) putting the quartz tube into an annealing furnace heated to 400 ℃, and preserving heat for 600 s;

The coercive force Hc of the annealed ribbon was 1.5A/m and the relative strain at break λ was 0.030.

Comparative example 5:

in this comparative example, the specific procedure was as follows:

(2) putting the quartz tube into an annealing furnace heated to 460 ℃, and preserving heat for 600 s;

The coercivity Hc of the ribbon after annealing was measured to be 4.3A/m and the relative strain at break λ was measured to be 0.016.

Comparative example 6:

in this comparative example, the specific procedure was as follows:

(2) putting the quartz tube into an annealing furnace heated to 490 ℃, and preserving heat for 600 s;

The X-ray diffraction test result shows that a part of crystalline alpha-Fe phase is precipitated in the sample. The coercive force Hc of the ribbon after the annealing treatment was 14.1A/m, B800 was 1.53T, and the relative strain at break λ was 0.023.

Comparative example 7:

in this comparative example, the specific procedure was as follows:

(2) putting the quartz tube into an annealing furnace heated to 520 ℃, and preserving heat for 600 s;

The X-ray diffraction test result shows that a more crystalline alpha-Fe phase and a partially crystalline Fe-B compound phase are precipitated in the sample. The coercive force Hc of the ribbon after the annealing treatment was 86.5A/m, B800 was 0.13T, and the relative strain at break λ was 0.010.

Comparative example 8:

in this comparative example, the specific procedure was as follows:

(2) putting the quartz tube into an annealing furnace heated to 430 ℃, and preserving heat for 5 s;

The X-ray diffraction test result shows that the sample still keeps an amorphous structure after the annealing treatment. The coercivity Hc of the annealed ribbon was measured to be 5.9A/m, B800 to be 1.29T, and the relative strain at break λ to be 1.0.

Comparative example 9:

in this comparative example, the specific procedure was as follows:

(2) putting the quartz tube into an annealing furnace heated to 430 ℃, and preserving heat for 10 s;

The X-ray diffraction test result shows that the sample still keeps an amorphous structure after the annealing treatment. The coercivity Hc of the annealed ribbon was measured to be 5.3A/m, B800 to be 1.28T, and the relative strain at break λ to be 1.0.

Comparative example 10:

in this comparative example, the specific procedure was as follows:

(2) putting the quartz tube into an annealing furnace heated to 430 ℃, and preserving heat for 20 s;

After the structure relaxation treatment was performed, the structure of the sample was tested using an X-ray diffractometer. The coercive force Hc of the sample was measured using a soft magnetic DC testing apparatus (maximum applied magnetic field of 800A/m). Bending the processed strip sample into a U shape, placing the U-shaped strip sample in two flat plates, enabling the two flat plates to gradually approach at a certain speed until the sample is broken or permanently deformed, and recording the distance between the two flat plates when the sample is broken as 2 gamma. Defining the relative breaking strain as: λ ═ t/(2 γ -t), where t is the thickness of the strip sample. If the sample does not break after permanent deformation, λ is 1. The larger the lambda value, the higher the toughness of the sample. The coercive force was measured to be 6.1A/m, B800 was 1.27T, and the relative strain at break λ was 1.0.

Comparative example 11:

in this comparative example, the specific procedure was as follows:

(2) putting the quartz tube into an annealing furnace heated to 430 ℃, and preserving heat for 30 s;

The X-ray diffraction test result shows that the sample still keeps an amorphous structure after the annealing treatment. The coercivity Hc of the annealed ribbon was measured to be 6.4A/m, B800 to be 1.31T, and the relative strain at break λ to be 1.0.

Comparative example 12:

in this comparative example, the specific procedure was as follows:

(2) putting the quartz tube into an annealing furnace heated to 430 ℃, and preserving heat for 40 s;

The X-ray diffraction test result shows that the sample still keeps an amorphous structure after the annealing treatment. The coercivity Hc of the annealed ribbon was measured to be 5.6A/m, B800 to be 1.35T, and the relative strain at break λ to be 1.0.

Comparative example 13:

in this comparative example, the specific procedure was as follows:

(2) putting the quartz tube into an annealing furnace heated to 430 ℃, and preserving heat for 50 s;

The X-ray diffraction test result shows that the sample still keeps an amorphous structure after the annealing treatment. The coercive force Hc of the ribbon after the annealing treatment was 5.0A/m, B800 was 1.33T, and the relative strain at break λ was 1.0.

Comparative example 14:

in this comparative example, the specific procedure was as follows:

(2) putting the quartz tube into an annealing furnace heated to 430 ℃, and preserving heat for 60 s;

The X-ray diffraction test result shows that the sample still keeps an amorphous structure after the annealing treatment. The coercivity Hc of the annealed ribbon was measured to be 5.2A/m, B800 to be 1.34T, and the relative strain at break λ to be 1.0.

As shown in table 1, when the lowest coercivity was not reached (not fully relaxed), and when the coercivity was similar, as in electric pulse treatment example 1, the coercivity was 3.8A/m; in comparative example 1, the coercive force was 3.7A/m, and the relative breaking strain (1.000) of the electric pulse treatment was much larger than that of the conventional annealing treatment (0.140). It shows that the electric pulse treatment can make the amorphous alloy have higher toughness when the coercive force is close before the amorphous alloy is completely relaxed.

As shown in FIG. 4, the strips had excellent toughness after the electric pulse parameter treatment described in example 3. As can be seen from table 1, the electric pulse parameters described in example 3 were also included. Very low coercivity (1.4A/m) and excellent toughness (relative strain to break of 1).

Industrial applicability

Compared with the traditional isothermal annealing heat treatment process, the structure relaxation method provided by the invention has the advantages of high efficiency, small temperature rise of the amorphous alloy sample and low sample temperature, and can effectively avoid the surface oxidation of the amorphous alloy. And the relaxation degree of the amorphous alloy structure can be effectively regulated and controlled, so that the amorphous alloy obtains more excellent performance and has good industrial practicability.

The present invention is not limited to the above embodiments, and any changes or substitutions that can be easily made by those skilled in the art within the technical scope of the present invention are also within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A method for relaxation of structure of amorphous alloy ribbon is characterized in that the method for relaxation of structure of amorphous alloy comprises the following steps:

(1) connecting two ends of the amorphous alloy strip sample with two electrodes or positive and negative electrodes of a pulse power supply respectively;

(2) placing the amorphous alloy strip sample in media with poor conductivity at different temperatures, and regulating and controlling the temperature of the sample;

(3) introducing pulse current, and controlling the pulse form, pulse width, pulse interval and current density of the electric pulse to realize the rapid relaxation of the amorphous alloy;

(4) in the electric pulse treatment process, the pulse form, pulse width, pulse interval and current density parameters of the electric pulse can be kept unchanged, and can also be adjusted in the treatment process or automatically adjusted according to preset parameters;

(5) after pulse current input to the amorphous alloy strip sample is stopped, regulating and controlling the cooling speed or the heating speed of the sample by adopting a method of placing the sample in media with different temperatures or contacting the sample with materials at different temperatures, namely regulating and controlling the cooling or heating speed of the sample from the temperature during processing to the subsequent set temperature;

wherein, the pulse form is AC pulse or DC pulse;

wherein the pulse width is 0.1-40 mus;

wherein the pulse interval is 1-1000 mus;

wherein the current density is 16.7-10000A/mm²；

The pulse current processing time is within 60 s;

the environment temperature of the sample can be regulated, and the sample temperature during the electric pulse treatment can be regulated by placing the sample in environment media with different temperatures and poor conductivity; the intermittent structural relaxation can be carried out on the amorphous alloy, wherein the intermittent electric pulse combined treatment can be carried out at different time intervals and by adopting different electric treatment parameters in the electric treatment process of the amorphous alloy strip sample.

2. Use of the method according to claim 1 for treating iron-based, cobalt-based, nickel-based amorphous alloy strip.

3. A continuous rapid structural relaxation method of amorphous alloy, which adopts the method of claim 1, characterized in that two electrodes or positive and negative electrodes of the pulse power supply in the step (1) are conductive rollers, the amorphous alloy strip is contacted with 2 conductive rollers, current is led into the amorphous strip in motion, and the amorphous strip is driven to move by traction of a driving wheel, so that the continuous structural relaxation treatment and the performance regulation of the amorphous alloy strip are realized.