Device for detecting magnetic anisotropy of ferromagnetic parts based on MBN method and use method thereof

Abstract

The present application relates to the technical field of ferromagnetic material nondestructive testing, more particularly, to a ferromagnetic part magnetic anisotropy detection device based on MBN method and a use method thereof.The detection device comprises a detection part, a signal generator and a signal processing part.The detection part comprises a single excitation coil and multiple receiving coils, wherein the receiving coils are adjusted in position by a movable arm assembly.The present application uses the combination of a single excitation coil and multiple receiving coils, can cover a larger detection area, is suitable for rapid measurement of large parts to be measured, and improves the detection efficiency.Moreover, the movable arm assembly ensures the adhesion of the receiving coils to the surface of the part to be measured, is suitable for different forms of parts to be measured, improves the versatility, and solves the poor versatility of the existing magnetic Barkhausen noise detection equipment.

Description

Technical Field

[0001] This invention relates to the field of nondestructive testing technology for ferromagnetic materials, and more specifically, to a device for detecting the magnetic anisotropy of ferromagnetic parts based on the MBN method, and a method for using the device. Background Technology

[0002] Ferromagnetic materials, with their excellent mechanical properties and relatively low economic cost, are widely used in critical structural components of electromechanical equipment in fields such as aerospace, marine engineering, rail transportation, mining machinery, petrochemicals, and defense. However, the failure of these critical structural components due to stress concentration, cracking, creep, and fatigue can have catastrophic consequences. Therefore, early damage warning for critical structural components is crucial for preventing safety accidents.

[0003] During the service life of ferromagnetic materials, damage such as cracks, stress concentration, fatigue, and creep alters the internal microstructure and stress state of the material, changing the preferred orientation process of the crystals within the ferromagnetic material and leading to macroscopic magnetic anisotropy. Magnetic Barkhausen noise detection technology, also known as the MBN method, is an active magnetic detection method. Based on its sensitivity to microstructure and stress, it can be used to detect the magnetic anisotropy behavior caused by factors such as microstructure, grain size, residual stress, hardened layer depth, carbon content, and creep in ferromagnetic materials.

[0004] Magnetic Barkhausen noise is a discontinuous and irreversible jump caused by the rotation of internal magnetic domains and the displacement of domain walls during the magnetization process of ferromagnetic materials. This jump induces a series of voltage pulse signals in the detection coil, which are called magnetic Barkhausen noise signals. The intensity of magnetic Barkhausen noise signals is closely related to the changes in the microstructure and stress state of the material. Based on the changes in the intensity of magnetic Barkhausen noise signals, the changes in the microstructure and stress state of the material can be inferred, thereby assessing the degree of damage to the ferromagnetic material.

[0005] However, existing magnetic Barkhausen noise detection technology is limited by its detection principle and equipment, requiring multiple or continuous measurements to accurately characterize the damage. Moreover, existing magnetic Barkhausen noise detection equipment has poor versatility, only capable of measuring planes or specific geometries, making it difficult to widely adopt this type of detection equipment. Summary of the Invention

[0006] Therefore, it is necessary to address the problem of poor versatility of existing magnetic Barkhausen noise detection equipment by providing a detection device and method for the magnetic anisotropy of ferromagnetic parts based on the MBN method.

[0007] This invention is achieved using the following technical solution:

[0008] In a first aspect, the present invention discloses a detection device for the magnetic anisotropy of ferromagnetic parts based on the MBN method, comprising: a detection unit, a signal generator, and a signal processing unit.

[0009] The detection unit includes an excitation module and a receiving module; the excitation module includes a base, a connecting rod, and an excitation coil; the connecting rod is located on the side of the base facing the part to be tested; the excitation coil is located at the end of the connecting rod away from the base; the receiving module includes N movable arm assemblies and receiving coils corresponding to the number of movable arm assemblies; wherein, the nth receiving coil is located at the end of the nth movable arm assembly away from the base; the movable arm assembly is connected to the base, and the position of the receiving coil is adjusted by the movable arm assembly; n∈[1,N].

[0010] The signal generator is used to provide an excitation voltage signal to the excitation coil. The signal processing unit is connected to the detection unit.

[0011] During testing, the excitation coil is pressed against surface A of the part under test, and the M receiving coils are pressed against surfaces B1 to B2 of the part under test, respectively. M Location, B1~B M Together with A, they form the target area, B1~B M The distances to A are equal, and 2 ≤ M ≤ N.

[0012] The signal generator inputs an excitation voltage signal to the excitation coil to magnetize the part under test and generate a magnetic Barkhausen noise signal during the magnetization process; M receiving coils receive the magnetic Barkhausen noise signal of the target area and transmit it to the signal processing unit; the signal processing unit analyzes the distribution pattern of the magnetic Barkhausen noise signal of the target area to obtain the magnetic anisotropy of the target area.

[0013] This device for detecting the magnetic anisotropy of ferromagnetic parts based on the MBN method implements the method or process according to embodiments of this disclosure.

[0014] Secondly, the present invention discloses a method for using the MBN-based detection device for the magnetic anisotropy of ferromagnetic parts as disclosed in the first aspect, comprising the following steps:

[0015] Step 1: Based on the testing requirements of the part to be tested, divide the area to be tested and the testing path of the part to be tested, and determine the displacement method of the testing unit;

[0016] Step 2: Adjust the excitation coil and the M receiving coils to the target area of ​​the part under test;

[0017] Step 3: Control the signal generator to input an excitation voltage signal to the excitation coil. M receiving coils receive the magnetic Barkhausen noise signal on the surface of the part under test and transmit it to the signal processing unit. The signal processing unit analyzes the distribution pattern of the magnetic Barkhausen noise signal on the surface of the part under test to obtain the magnetic anisotropy of the target area of ​​the part under test.

[0018] Step 4: Following the displacement method determined in Step 1, move the detection unit along the detection path and cover all the detection areas of the part to be tested.

[0019] The method of using the MBN-based device for detecting the magnetic anisotropy of ferromagnetic parts implements the method or process according to embodiments of this disclosure.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. This invention combines a single excitation coil with multiple receiving coils, which can cover a larger detection area and is suitable for rapid measurement of large parts under test. It avoids the problem of a small measurement area per measurement by a traditional single receiving coil and improves detection efficiency. Moreover, the movable arm assembly ensures the contact between the receiving coil and the surface under test, and can be applied to parts under test of different shapes, thus improving versatility.

[0022] 2. This invention uses a single excitation coil, eliminating the need for frequent disassembly and enabling continuous detection. By repeatedly measuring the defect location with multiple receiving coils during continuous measurement, this invention overcomes the drawback of traditional magnetic Barkhausen noise detection, which is susceptible to external environmental interference. Attached Figure Description

[0023] Figure 1 This is a structural diagram of the device for detecting the magnetic anisotropy of ferromagnetic parts based on the MBN method in Embodiment 1 of the present invention;

[0024] Figure 2 for Figure 1 A magnified view of a portion of the image;

[0025] Figure 3 For use in Embodiment 1 of the present invention Figure 1 A schematic diagram of the detection device performing detection under operating condition 1;

[0026] Figure 4 For use in Embodiment 1 of the present invention Figure 1 A schematic diagram of the detection device performing detection under operating condition 2;

[0027] Figure 5 For use in Embodiment 1 of the present invention Figure 1 Another schematic diagram of the detection device performing detection under operating condition 2;

[0028] Figure 6 For use in Embodiment 1 of the present invention Figure 1 A schematic diagram of the detection device performing detection under operating condition 3;

[0029] Figure 7 For use in Embodiment 1 of the present invention Figure 1 A schematic diagram of the detection device performing detection under operating condition 4;

[0030] The attached diagram lists the components represented by each number as follows:

[0031] 1. Base, 2. Slider, 3. Movable arm one, 4. Movable arm two, 5. Connecting rod, 6. Receiving coil, 7. Signal generator, 8. Power amplifier, 9. Hinge one, 10. Hinge two, 11. Multi-channel data acquisition card, 12. Industrial computer, 13. Excitation coil, 14. Part under test. Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] It should be noted that when a component is said to be "installed on" another component, it can be directly on the other component or it may be in a component that is centered on it. When a component is said to be "set on" another component, it can be directly set on the other component or it may also be in a component that is centered on it. When a component is said to be "fixed to" another component, it can be directly fixed to the other component or it may also be in a component that is centered on it.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "or / and" as used herein includes any and all combinations of one or more of the associated listed items.

[0035] Example 1

[0036] Please see Figure 1 , Figure 1 This is a structural diagram of a device for detecting the magnetic anisotropy of ferromagnetic parts based on the MBN method.

[0037] like Figure 1 As shown, the detection device includes: a detection unit, a signal generator 7, and a signal processing unit.

[0038] First, let's look at the testing department: The testing department includes an excitation module and a receiving module.

[0039] The excitation module includes a base 1, a connecting rod 5, and an excitation coil 13. The connecting rod 5 is fixed to the side of the base 1 facing the part 14 to be tested. The excitation coil 13 is mounted on the end of the connecting rod 5 away from the base 1. In this embodiment 1, the excitation coil 13 is made of high-permeability ferrite with polyester enameled wire winding and is mounted on the connecting rod 5.

[0040] The receiving module includes N movable arm assemblies and receiving coils 6 corresponding to the number of movable arm assemblies. The nth receiving coil 6 is installed at the end of the nth movable arm assembly furthest from the base 1. The movable arm assemblies are connected to the base 1, and the position of the receiving coil 6 is adjusted by the movable arm assemblies; n∈[1,N].

[0041] The movable arm assembly is a structure with multiple degrees of freedom and positioning capability. Existing robotic arms can be used for the movable arm assembly, but this would result in higher costs.

[0042] Therefore, in this embodiment 1, the movable arm assembly, base 1, etc., are independently designed:

[0043] N slide rails are evenly mounted around the base 1, and these N slide rails are parallel to the axis of the base 1. Each slide rail is equipped with a slider 2. The nth movable arm assembly is connected to the nth slider 2. When the nth movable arm assembly moves along the nth slide rail with the nth slider 2, the distance between the nth receiving coil 6 and the part 14 to be measured changes accordingly. It should be noted that the slider 2 is slidably connected to the slide rail and has a certain amount of friction; only under a sufficiently large external force will the slider 2 move relative to the slide rail. The movable arm assembly includes movable arm one 3, movable arm two 4, hinge one 9, and hinge two 10. Hinge one 9 rotatably connects movable arm one 3 to slider 2. Hinge two 10 rotatably connects movable arm two 4 to movable arm one 3. The receiving coil 6 is mounted on the end of movable arm two 4 away from hinge two 10. In this embodiment 1, the receiving coil 6 is also made of high-permeability ferrite with polyester enameled wire winding and is mounted on movable arm two 4.

[0044] In this way, by rotating hinge 9 and hinge 10, the angle and position of the receiving coil 6 can be adjusted. It should be noted that hinge 9 and hinge 10 are both friction-rotating structures with a certain degree of damping; they will only rotate under a sufficiently large external force. Thus, after each adjustment of the movable arm assembly, the assembly can automatically reposition itself.

[0045] Next, consider signal generator 7. Signal generator 7 is used to provide an excitation voltage signal to excitation coil 13. Signal generator 7 has the function of adjusting the voltage frequency, voltage amplitude, and voltage waveform of the signal. The signal generator 7 selected in this embodiment 1 has the following specifications: voltage frequency range of 0Hz to 1000Hz; voltage amplitude of 0V to 20V; and voltage waveform selectable from triangular wave and sine wave.

[0046] Generally, considering the influence of signal strength, a power amplifier 8 can be connected to the signal generator 7. That is, the signal generator 7 is connected to the excitation coil 13 through the power amplifier 8, which effectively amplifies the excitation voltage signal to the excitation coil 13.

[0047] Next, let's look at the signal processing unit, which is connected to the detection unit. Specifically, the signal processing unit includes a multi-channel data acquisition card 11 and an industrial control computer 12. The multi-channel data acquisition card 11 is used to acquire the magnetic Barkhausen noise signal of the target area. The industrial control computer 12 is used to process the signals acquired by the multi-channel data acquisition card 11 to obtain the magnetic anisotropy of the target area.

[0048] In this embodiment 1, the multi-channel data acquisition card 11 sets the acquisition frequency for the magnetic Barkhausen noise signal to 20Hz-500kHz. Additionally, the multi-channel data acquisition card 11 also acquires the excitation voltage signal at a frequency of 0Hz-400Hz to distinguish the rising and falling segments of the signal, as well as the starting position of the magnetic Barkhausen noise signal.

[0049] In general, during testing, the excitation coil 13 is pressed against surface A of the part to be tested 14. Based on the testing requirements, M receiving coils 6 are selected from N receiving coils 6, and these M receiving coils 6 are pressed against surfaces B1 to B2 of the part to be tested 14. M Location. B1~B M Together with A, they form the target area, B1~B M The distances to A are equal; 2 ≤ M ≤ N.

[0050] It should be noted that, due to B1~B M The statement that B1 is equidistant from A means that B1 is equidistant from A by a distance L1, B2 is equidistant from A by a distance L2, ..., B... M Distance L from A M L1, L2, ..., L M Equal. For example... Figure 2 As shown, this illustrates the case where M=2, where the distance between B1 and A is equal to the distance between B2 and A.

[0051] The signal generator 7 inputs an excitation voltage signal to the excitation coil 13, magnetizing the part under test 14 and generating a magnetic Barkhausen noise signal during the magnetization process. M receiving coils 6 receive the magnetic Barkhausen noise signal from the target area and transmit it to the signal processing unit. The signal processing unit analyzes the distribution pattern of the magnetic Barkhausen noise signal in the target area to obtain the magnetic anisotropy of the target area. Of course, the magnetic anisotropy of the target area can be used to further analyze whether there are defects in the target area.

[0052] Because it uses multiple receiving coils, this detection device can perform multiple measurements on a given area. The operation is also very convenient: move the detection unit so that the M receiving coils 6 pass sequentially through the area, then select the magnetic Barkhausen noise signals at corresponding times according to the time sequence of the receiving coils 6 passing through the area, and take the average value to obtain an accurate magnetic Barkhausen noise signal. Compared to existing single receiving coil methods, this method is faster and more accurate.

[0053] In addition, the detection device is equipped with a power supply. Generally, a built-in rechargeable power supply can be used, or an external power supply can be used.

[0054] In simple terms, the combination of a single excitation coil and multiple receiving coils in this invention allows multiple receiving coils 6 with the same test parameters to receive signals from the detection area, enabling multiple measurements of the area under test and improving the accuracy of the detection.

[0055] The method of using the detection device of Example 1 is also disclosed, including the following steps:

[0056] Step 1: Based on the testing requirements of the part to be tested 14, divide the area to be tested and the testing path of the part to be tested 14, and determine the displacement method of the testing unit.

[0057] In step 1, the shape of the area to be detected includes a sector, a circle, a rectangle, etc. The shape of the detection path includes an arc, a circle, a straight line, etc. The displacement method includes moving, rotating, etc.

[0058] Step 2: Adjust the excitation coil 13 and the receiving coil 6 to the target area of ​​the part under test 14.

[0059] Specifically, the excitation coil 13 is pressed at point A, and the required M receiving coils 6 are selected from the N receiving coils 6. The M receiving coils 6 are then adjusted by the corresponding M movable arm assemblies to press them onto the surfaces B1 to B1 of the part to be tested 14. M Location. Among them, B1 to B M A encloses the target area, B1 to B2. M The distances to A are the same; 2≤M≤N.

[0060] Step 3: The control signal generator 7 inputs an excitation voltage signal to the excitation coil 13. M receiving coils 6 receive the magnetic Barkhausen noise signal on the surface of the part under test 14 and transmit it to the signal processing unit. The signal processing unit analyzes the distribution pattern of the magnetic Barkhausen noise signal on the surface of the part under test 14 and obtains the magnetic anisotropy of the target area of ​​the part under test 14.

[0061] Step 4: Following the displacement method determined in Step 1, move the detection unit along the detection path and cover all the detection areas of the part 14 to be tested.

[0062] The following examples (i.e., different working conditions) illustrate the selection of the above steps:

[0063] 1. See Figure 3 The surface to be measured of the part 14 is a plane, and the area to be inspected is a rectangular area on the plane. Therefore, the inspection path is generally set to a straight line, and the displacement method is generally set to a moving type (moving along the straight inspection path).

[0064] Specifically, two receiving coils 6 are selected, and the two receiving coils 6 are symmetrically set to excite the coil 13. The three coils press against the rectangular area, and the target area formed by the three coils covers the rectangular area in the width direction. By moving the three coils along the length direction of the rectangular area, full coverage of the rectangular area can be achieved. Of course, the target area formed by the three coils can also cover the rectangular area in the length direction, and the three coils can be moved along the width direction of the rectangular area to achieve full coverage of the rectangular area.

[0065] 2. The surface to be tested of the part 14 is an arc surface, and the area to be tested is a rectangular area on the arc surface. The length direction of the rectangular area is a straight line, and the width direction is an arc.

[0066] See Figure 4 The detection path can be set to a straight line, and the displacement method can be set to moving (moving along the straight detection path). Specifically, select two receiving coils 6 and set the two receiving coils 6 to symmetrically excite the coil 13; press the three coils against the rectangular area, and the target area composed of the three coils covers the rectangular area in the width direction of the rectangular area. Move the three coils along the length direction of the rectangular area to achieve full coverage of the rectangular area.

[0067] See Figure 5The detection path can also be set to an arc shape, and the displacement method can be set to moving (moving along the arc-shaped detection path). Specifically, select two receiving coils 6 and set the two receiving coils 6 to symmetrically excite the coil 13; press the three coils against the rectangular area, and the target area composed of the three coils covers the rectangular area in the length direction of the rectangular area. Move the three coils along the width direction of the rectangular area to achieve full coverage of the rectangular area.

[0068] 3. See Figure 6 The surface to be measured of the part 14 is a plane, and the area to be detected is a circular area on the plane. Therefore, the detection path is generally set to a circle, and the displacement method is generally set to a rotational type (the receiving coil 6 rotates around the excitation coil 13).

[0069] Specifically, select two receiving coils 6 and set the two receiving coils symmetrically to excite the coil 13; press the three coils against the rectangular area, and make the excitation coil 13 coincide with the center of the circular area. The target area formed by the three coils covers the radius of the circular area. With the excitation coil 13 as the center, make the receiving coil 6 rotate around the excitation coil 13, thereby achieving full coverage of the circular area.

[0070] 4. See Figure 7 If the surface to be measured of the part to be measured 14 is a plane and the area to be detected is a sector on the plane, then the detection path is generally set to an arc shape and the displacement method is generally set to a rotational type (the receiving coil 6 rotates around the excitation coil 13).

[0071] Specifically, two receiving coils 6 are selected, and the two receiving coils 6 are symmetrically set with excitation coils 13; the three coils press against the rectangular area, and the excitation coils 13 coincide with the center of the circle where the sector area is located. The target area formed by the three coils covers the radius of the circle where the sector area is located. With the excitation coils 13 as the center, the receiving coils 6 are rotated around the excitation coils 13, thereby achieving full coverage of the sector area.

[0072] The examples above are not exhaustive; in actual use, you can choose according to the specific circumstances.

[0073] However, compared with existing technologies, this detection device, when used in conjunction with the above-mentioned method, has the following advantages:

[0074] 1) The single-excitation, multiple-receiver detection method effectively increases the detection area;

[0075] 2) Multiple receiving coils 6 facilitate multiple measurements of the area under test, improving the accuracy of detection;

[0076] 3) Multiple movable arm assemblies can be adapted to test parts of different shapes by adjusting the appropriate angle.

[0077] Example 2

[0078] Example 2 is derived from Example 1. For the signal processing unit, the better the quality of the acquired magnetic Barkhausen noise signal, the more accurate the processed result. However, the magnetic Barkhausen noise signal is affected by the excitation voltage signal; therefore, it is necessary to determine the optimal excitation voltage parameters—the optimal excitation voltage amplitude and the optimal excitation voltage frequency.

[0079] In Example 2, the excitation coil 13 is also equipped with a Hall sensor to detect the magnetic flux density at point A, thereby determining the optimal excitation voltage amplitude. Specifically, the detection data from the Hall sensor is acquired by the multi-channel data acquisition card 11 to obtain the magnetic flux density at point A. The industrial control computer 12 also calculates the power spectrum based on the magnetic Barkhausen noise signal of the target area to determine the optimal excitation voltage frequency.

[0080] The detection device of Example 2 is used in a similar way to Example 1. In step 3, the signal generator 7 is adjusted to obtain the optimal excitation voltage amplitude and the optimal excitation voltage frequency. The excitation voltage signal is controlled according to the optimal excitation voltage amplitude and the optimal excitation voltage frequency.

[0081] Specifically, the debugging method for signal generator 7 includes:

[0082] Set the excitation voltage signal to a sinusoidal form and input the first round of test excitation voltage from 0V to 20V sequentially to the excitation coil 13 at 0.5V intervals; obtain the magnetic induction intensity at point A, and select the first round of test excitation voltage amplitude corresponding to the maximum magnetic induction intensity at point A as the optimal excitation voltage amplitude;

[0083] The excitation voltage signal is controlled with the optimal excitation voltage amplitude. The second round of test excitation voltage from 0Hz to 1000Hz is sequentially input to the excitation coil 13 at 10Hz intervals. The magnetic Barkhausen noise signal of the target area is acquired and the power spectrum is calculated. The second round of test excitation voltage frequency corresponding to the maximum power spectrum value is selected as the optimal excitation voltage frequency.

[0084] The formula for calculating the power spectrum is as follows: E represents the power spectrum, V Rms t represents the root mean square envelope of the receiving coil voltage, and t represents time.

[0085] By controlling the excitation voltage signal according to the optimal excitation voltage amplitude and frequency, a high-quality magnetic Barkhausen noise signal can be obtained, thereby ensuring the accuracy of the magnetic anisotropy detection results.

[0086] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0087] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A device for detecting the magnetic anisotropy of ferromagnetic parts based on the MBN method, characterized in that, include: The detection part comprises an excitation module and a receiving module; the excitation module comprises a base, a connecting rod and an excitation coil; the connecting rod is arranged on the side of the base facing the part to be detected; the excitation coil is arranged at the end of the connecting rod away from the base; the receiving module comprises N one movable arm assembly and a receiving coil corresponding to the number of movable arm assemblies; wherein the first n receiving coil is arranged at the end of the first n movable arm assembly away from the base; the movable arm assembly is connected with the base, and the position of the receiving coil is adjusted through the movable arm assembly; n ∈[1, N ]; the base is uniformly provided with N slides in the circumferential direction, N the slides are parallel to the axial direction of the base, and each slide is provided with a sliding block; wherein the first n movable arm assembly is connected with the first n sliding block. A signal generator, used to provide an excitation voltage signal to the excitation coil; and The signal processing unit is connected to the detection unit; In the detection, the exciting coil presses on the surface A of the part to be detected, M The receiving coils respectively press on the surfaces B1~B M of the part to be detected, M B1~B M and A enclose a target area, the distances from B1~B M to A are equal, 2≤ N ​ The signal generator inputs an excitation voltage signal to the excitation coil, magnetizes the part to be tested, and generates a magnetic Barkhausen noise signal during the magnetization process; M The receiving coil receives the magnetic Barkhausen noise signal of the target area and transmits it to the signal processing unit. The signal processing unit analyzes the distribution rule of the magnetic Barkhausen noise signal of the target area and obtains the magnetic anisotropy of the target area.

2. The device for detecting the magnetic anisotropy of a ferromagnetic part based on the MBN method according to claim 1, characterized in that, The signal generator is connected to the excitation coil via a power amplifier; The excitation coil is also equipped with a Hall sensor to detect the magnetic induction intensity at point A in order to determine the optimal excitation voltage amplitude.

3. The device for detecting the magnetic anisotropy of a ferromagnetic part based on the MBN method according to claim 1, characterized in that, Both the excitation coil and the receiving coil are made of high-permeability ferrite with polyester enameled wire winding.

4. The apparatus for detecting the magnetic anisotropy of a ferromagnetic part based on the MBN method according to claim 1, characterized in that, The movable arm assembly includes: One movable arm; Two movable arms; Hinge 1, which is used to rotatably connect movable arm 1 to slider; and Hinge 2 is used to rotatably connect movable arm 2 to movable arm 1; the receiving coil is located at the end of movable arm 2 away from hinge 2.

5. The apparatus for detecting the magnetic anisotropy of a ferromagnetic part based on the MBN method according to claim 1, characterized in that, The signal processing unit includes: A multi-channel data acquisition card is used to acquire magnetic Barkhausen noise signals in the target area; and An industrial control computer is used to process the signals acquired by the multi-channel data acquisition card to obtain the magnetic anisotropy of the target area; the industrial control computer also calculates the power spectrum based on the magnetic Barkhausen noise signal of the target area to determine the optimal excitation voltage frequency.

6. The apparatus for detecting the magnetic anisotropy of a ferromagnetic part based on the MBN method according to claim 1, characterized in that, The device for detecting the magnetic anisotropy of ferromagnetic parts based on the MBN method also includes an external power supply for powering the device.

7. A method of using the apparatus for detecting the magnetic anisotropy of ferromagnetic parts based on the MBN method according to any one of claims 1 to 6, characterized in that, Includes the following steps: Step 1: Based on the testing requirements of the part to be tested, divide the area to be tested and the testing path of the part to be tested, and determine the displacement method of the testing unit; Step 2, adjusting the excitation coil, M one of the receiving coils to a target area of the part under test; Step 3, controlling the signal generator to input an excitation voltage signal to the excitation coil, M The receiving coil receives the magnetic Barkhausen noise signal of the surface of the part to be tested and transmits it to the signal processing unit; the signal processing unit analyzes the distribution rule of the magnetic Barkhausen noise signal of the surface of the part to be tested to obtain the magnetic anisotropy of the target region of the part to be tested. Step 4: Following the displacement method determined in Step 1, move the detection unit along the detection path and cover all the detection areas of the part to be tested.

8. The method of using the apparatus for detecting the magnetic anisotropy of ferromagnetic parts based on the MBN method according to claim 7, characterized in that, In step 1, the shape of the area to be detected includes, but is not limited to, a fan shape, a circle, and a rectangle; the shape of the detection path includes, but is not limited to, an arc shape, a circle, and a straight line; and the displacement method includes, but is not limited to, a moving type and a rotating type. In step 4, when the detection path is straight, the displacement method is a moving type, and the entire detection unit moves along the straight detection path; when the detection path is arc-shaped or circular, the displacement method is a rotating type, and the receiving coil rotates around the excitation coil.

9. The method of using the apparatus for detecting the magnetic anisotropy of ferromagnetic parts based on the MBN method according to claim 7, characterized in that, In step 3, The signal generator was adjusted to obtain the optimal excitation voltage amplitude and the optimal excitation voltage frequency. The excitation voltage signal is controlled based on the optimal excitation voltage amplitude and optimal excitation voltage frequency. The debugging method for the signal generator includes: Set the excitation voltage signal to a sinusoidal form, and input the first round of test excitation voltage from 0V to 20V sequentially to the excitation coil at 0.5V intervals; obtain the magnetic induction intensity at point A, and select the first round of test excitation voltage amplitude corresponding to the maximum magnetic induction intensity at point A as the optimal excitation voltage amplitude; The excitation voltage signal is controlled with the optimal excitation voltage amplitude. The second round of test excitation voltage from 0Hz to 1000Hz is sequentially input to the excitation coil at 10Hz intervals. The magnetic Barkhausen noise signal of the target area is acquired and the power spectrum is calculated. The second round of test excitation voltage frequency corresponding to the maximum power spectrum value is selected as the optimal excitation voltage frequency.

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