CN113670483A - Method and device for measuring dynamic Barkhausen noise stress - Google Patents
Method and device for measuring dynamic Barkhausen noise stress Download PDFInfo
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- CN113670483A CN113670483A CN202110978575.0A CN202110978575A CN113670483A CN 113670483 A CN113670483 A CN 113670483A CN 202110978575 A CN202110978575 A CN 202110978575A CN 113670483 A CN113670483 A CN 113670483A
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- 230000005330 Barkhausen effect Effects 0.000 title claims abstract description 84
- 238000000034 method Methods 0.000 title claims abstract description 12
- 230000005291 magnetic effect Effects 0.000 claims abstract description 71
- 239000003302 ferromagnetic material Substances 0.000 claims abstract description 55
- 238000005259 measurement Methods 0.000 claims abstract description 11
- 230000005415 magnetization Effects 0.000 claims description 7
- 230000005284 excitation Effects 0.000 claims description 6
- 239000000523 sample Substances 0.000 claims description 5
- 230000035699 permeability Effects 0.000 claims description 3
- 239000000463 material Substances 0.000 abstract description 3
- 230000005294 ferromagnetic effect Effects 0.000 abstract description 2
- 238000001514 detection method Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 230000009191 jumping Effects 0.000 description 2
- 230000005381 magnetic domain Effects 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000003321 amplification Effects 0.000 description 1
- 239000007822 coupling agent Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 230000001939 inductive effect Effects 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 238000009659 non-destructive testing Methods 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L1/00—Measuring force or stress, in general
- G01L1/12—Measuring force or stress, in general by measuring variations in the magnetic properties of materials resulting from the application of stress
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L5/00—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
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- Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
Abstract
The invention discloses a method and a device for measuring dynamic Barkhausen noise stress, which magnetizes a ferromagnetic material through a constant magnetic field; the constant magnetic field and the ferromagnetic material move relatively to induce Barkhausen noise in the ferromagnetic material; acquiring a live Barkhausen noise signal by using a live Barkhausen noise signal pickup unit; and calculating the stress of the ferromagnetic material by adopting the motional Barkhausen noise signal. The problem of stress on-line measurement in the scene of high-speed movement of ferromagnetic material components is effectively solved, and the measurement precision is more reliable and accurate. The device can be used for measuring the stress of a planar plate with a large surface area extension by moving on the surface of a ferromagnetic material, and can also be used for measuring the stress of a ferromagnetic pipe, a wire and a wire material on line in a mode that the ferromagnetic material passes through the middle of a dynamic Barkhausen noise stress measuring device.
Description
Technical Field
The invention relates to the technical field of nondestructive testing, in particular to a method and a device for measuring motional Barkhausen noise stress based on constant magnetic field excitation.
Background
The ferromagnetic material is a main material of a key bearing structural member of the high-speed motor train unit. Under the stress action of long-term complex load, the ferromagnetic material force-bearing part is easy to generate stress concentration, and the stress distribution of the ferromagnetic material greatly determines the fatigue life of the ferromagnetic material part. The Barkhausen noise detection technology has the advantages of no need of a coupling agent, high sensitivity, high measurement precision and the like, is widely applied to stress measurement of ferromagnetic materials, but in the on-line detection application of high-speed movement of high-speed motor train units and the like, the traditional Barkhausen detection method adopting alternating current magnetization is limited by a magnetization method, and cannot measure the stress condition of the ferromagnetic materials during high-speed movement.
Disclosure of Invention
The invention aims to overcome the defects of the prior art, provides a method and a device for measuring the dynamic Barkhausen noise stress based on constant magnetic field excitation, and aims to solve the problem that the existing stress measuring method cannot measure the stress of a ferromagnetic material member moving at high speed.
In order to achieve the purpose, the invention adopts the following technical scheme. A method for measuring the dynamic Barkhausen noise stress comprises the following steps:
1) magnetizing the ferromagnetic material by a constant magnetic field;
2) the constant magnetic field and the ferromagnetic material move relatively to induce Barkhausen noise in the ferromagnetic material;
3) the Barkhausen noise is motional Barkhausen noise, and a motional Barkhausen noise signal pickup unit is adopted to acquire a motional Barkhausen noise signal;
4) and calculating the stress of the ferromagnetic material by adopting the motional Barkhausen noise signal.
Further, the value of the constant magnetic field is the magnetic field intensity Hm when the ferromagnetic material to be measured reaches the saturation magnetization Ms.
A device for measuring the stress of the dynamic Barkhausen noise comprises a constant magnetic field generating unit, a magnetic field guiding unit, a dynamic Barkhausen noise signal picking unit and a dynamic Barkhausen noise signal processing unit, wherein the constant magnetic field generating unit, the magnetic field guiding unit and the dynamic Barkhausen noise signal picking unit are fixedly packaged into an integral probe; the constant magnetic field generating unit is used for generating a constant magnetic field; the magnetic field guiding unit is used for setting a constant magnetic field path; the motional Barkhausen noise signal pickup unit is used for picking up motional Barkhausen noise signals generated by the excitation of a constant magnetic field; the dynamic Barkhausen noise signal processing unit is used for calculating a stress value after data processing is carried out on the dynamic Barkhausen noise signal of the dynamic Barkhausen noise signal pickup unit.
Further, the constant magnetic field generating unit is composed of a direct current electromagnet or a permanent magnet.
Further, the relative motion between the device body and the ferromagnetic material is linear relative motion or curvilinear relative motion.
Further, the device body is located on the surface of the ferromagnetic material.
Further, the ferromagnetic material may be passed through the inside of the device body.
Further, the motional barkhausen noise signal pickup unit is a magnetic sensing element.
Further, the relative permeability of the magnetic field guiding unit is more than 1.
The invention effectively solves the problem of online stress measurement in the scene of high-speed movement of the ferromagnetic material component by adopting the constant magnetic field to induce the motive Barkhausen noise in the ferromagnetic material while moving relative to the ferromagnetic material. The constant magnetic field is adopted to induce the Barkhausen noise signal, the constant magnetic field is easier to generate in practical application, compared with an alternating-current magnetic field, the electromagnetic interference generated by the alternating-current magnetic field is small, the constant magnetic field and the signal pickup unit are relatively static, the interference signal cannot be generated in the dynamic Barkhausen noise signal pickup unit, and the measurement precision of the dynamic Barkhausen noise stress measurement device is more reliable and accurate. The device can be used for measuring the stress of a planar plate with a large surface area extension by moving on the surface of a ferromagnetic material, and can also be used for measuring the stress of a ferromagnetic pipe, a wire and a wire material on line in a mode that the ferromagnetic material passes through the middle of a dynamic Barkhausen noise stress measuring device.
Drawings
FIG. 1 is a flow chart of a method of the present invention;
FIG. 2 is a schematic view of the structure of a U-shaped electromagnet or permanent magnet according to the present invention;
FIG. 3 is a schematic view of the structure of a rectangular parallelepiped type electromagnet or permanent magnet according to the present invention;
FIG. 4 is a diagram of background noise picked up by the signal pickup unit of the present invention;
FIG. 5 is a schematic diagram of the motional Barkhausen noise picked up by the signal pick-up unit of the present invention;
FIG. 6 is a graph comparing the measured results with actual values for the device of the present invention;
FIG. 7 is a schematic size diagram of a ferromagnetic material of the present invention;
FIG. 8 is a graph of magnetization in the present invention;
in the figure: 100. the device comprises a device body, 1, a constant magnetic field generating unit, 2, a magnetic field guiding unit, 3, a mobile Barkhausen noise signal pickup unit, 4, a mobile Barkhausen noise signal processing unit, 5, a probe and 6, wherein the constant magnetic field generating unit is arranged on the device body.
Detailed Description
The invention will be further explained with reference to the drawings and the embodiments. See fig. 1-8.
A method for measuring the dynamic Barkhausen noise stress comprises the following steps:
1) as shown in fig. 1, a constant magnetic field generating unit 1 is disposed on the surface of the ferromagnetic material 6 (as shown in fig. 2 and 3) for generating a constant magnetic field, and the electromagnet or permanent magnet of the magnetic field guiding unit 2 sets a magnetic path of the constant magnetic field that magnetizes the ferromagnetic material 6 in a fixed direction S100;
2) the constant magnetic field in step 1) and the ferromagnetic material 6 make relative motion S200, as shown in fig. 2 and 3, to the right, thereby inducing barkhausen noise S300 in the ferromagnetic material 6;
3) in the step 2), the Barkhausen noise signal is induced by the relative motion of the constant magnetic field and the ferromagnetic material 6, and is motional Barkhausen noise, the ferromagnetic material adopts Q235 steel, and the size is shown in figure 7. A receiving coil with the wire diameter of 0.05mm and the number of turns of 1000 turns is used as a dynamic Barkhausen noise signal pickup unit 3, the coil is positioned at the center below a U-shaped electromagnet or a permanent magnet or is positioned at a short distance (as shown in figures 2 and 3) of the cuboid electromagnet or the permanent magnet, and then the dynamic Barkhausen noise signal is picked up, and the waveforms of signals picked up by the receiving coil before and after relative motion occurs are respectively shown in figures 4 and 5; the value of the constant magnetic field is set to the magnetic field strength Hm at which the ferromagnetic material 6 reaches the saturation magnetization Ms during magnetization (as shown in fig. 8).
4) As shown in fig. 1, the receiving coil transmits the picked-up signal to the motional barkhausen noise signal processing unit 4 for amplification, filtering, and the like, and finally transmits the signal to the upper computer to calculate the stress of the ferromagnetic material 6 by using the motional barkhausen noise signal S400.
According to the measuring steps, the motional Barkhausen noise stress measuring device based on the excitation of the constant magnetic field is provided, wherein:
the constant magnetic field generating unit 1, the magnetic field guiding unit 2, the motional barkhausen noise signal pickup unit 3 and the motional barkhausen noise signal processing unit 4 constitute an integrated device 100 of the motional barkhausen noise stress measurement method based on the constant magnetic field excitation. The constant magnetic field generating unit 1 is composed of an electromagnet and a permanent magnet, and the generated constant magnetic field magnetizes the ferromagnetic material 6 along the near surface of the ferromagnetic material. The magnetic field guiding unit 2 is used for setting a specific magnetic field path, when the constant magnetic field generating unit 1 and the ferromagnetic material 6 generate relative motion, the ferromagnetic material 6 can generate magnetic domain inversion and magnetic domain wall jumping, further generate 'Barkhausen jumping' to generate dynamic Barkhausen noise, the dynamic Barkhausen noise signal pickup unit 3 composed of a receiving coil picks up the dynamic Barkhausen noise signal and then transmits the signal to the dynamic Barkhausen noise signal processing unit 4, the Barkhausen noise signal processing unit 4 is composed of a filter, a signal amplifying circuit and the like, wherein the filter adopts an active filter, the signal amplifying circuit adopts an AD620 module, and linear power supplies are used for all the signals. And finally, a series of data processing is carried out, and the data are transmitted to an upper computer, so that the stress value of the ferromagnetic material 6 is calculated.
The constant magnetic field generating unit 1 generates a constant magnetic field, including but not limited to, generating a constant magnetic field using a dc electromagnet or generating a constant magnetic field using a permanent magnet, which is in a shape including but not limited to a U-shape or a rectangular parallelepiped shape.
The constant magnetic field generating unit 1, the magnetic field guiding unit 2 and the mobile Barkhausen noise signal pickup unit 3 are fixedly connected and packaged into a whole probe 5, and the mobile Barkhausen noise signal processing unit 4 picks up the mobile Barkhausen noise signal through a receiving coil in the cable lead receiving probe 5. The relative permeability of the magnetic field guiding element 2 is much greater than 1. The signal pickup unit 3 picks up the motional barkhausen noise signal by using a magnetic sensor.
The integrated device 100 for measuring the dynamic Barkhausen noise stress and the ferromagnetic material 6 must move relatively, and the relative movement mode includes but is not limited to linear movement and curvilinear movement.
The relative position of the integrated device 100 for measuring dynamic barkhausen noise stress and the ferromagnetic material 6 includes, but is not limited to, the integrated device 100 for measuring dynamic barkhausen noise stress being placed on the surface of the ferromagnetic material 6 or the ferromagnetic material 6 passing through the integrated device 100 for measuring dynamic barkhausen noise stress.
The device 100 of the invention tests a plurality of groups of data on the ferromagnetic material 6, calculates the stress value by the upper computer and compares the stress value with the preset actual stress value (as shown in figure 6), has higher measurement precision and accuracy, and effectively solves the problem of stress measurement of the ferromagnetic material under the condition of high-speed movement.
Claims (9)
1. A method for measuring the dynamic Barkhausen noise stress is characterized by comprising the following steps:
1) magnetizing the ferromagnetic material by a constant magnetic field;
2) the constant magnetic field and the ferromagnetic material move relatively to induce Barkhausen noise in the ferromagnetic material;
3) the Barkhausen noise is motional Barkhausen noise, and a motional Barkhausen noise signal pickup unit is adopted to acquire a motional Barkhausen noise signal;
4) and calculating the stress of the ferromagnetic material by adopting the motional Barkhausen noise signal.
2. The method of claim 1, wherein the constant magnetic field is selected to be a magnetic field Hm at which the ferromagnetic material to be measured reaches saturation magnetization Ms.
3. The device for measuring the dynamic Barkhausen noise stress is characterized in that the device body consists of a constant magnetic field generating unit, a magnetic field guiding unit, a dynamic Barkhausen noise signal picking unit and a dynamic Barkhausen noise signal processing unit, wherein the constant magnetic field generating unit, the magnetic field guiding unit and the dynamic Barkhausen noise signal picking unit are fixedly packaged into an integral probe; the constant magnetic field generating unit is used for generating a constant magnetic field; the magnetic field guiding unit is used for setting a constant magnetic field path; the motional Barkhausen noise signal pickup unit is used for picking up motional Barkhausen noise signals generated by the excitation of a constant magnetic field; the dynamic Barkhausen noise signal processing unit is used for calculating a stress value after data processing is carried out on the dynamic Barkhausen noise signal of the dynamic Barkhausen noise signal pickup unit.
4. The device for measuring dynamic Barkhausen noise stress according to claim 3, wherein the constant magnetic field generating unit is constituted by a DC electromagnet or a permanent magnet.
5. The device for measuring the dynamic Barkhausen noise stress according to claim 3, wherein the relative movement between the device body and the ferromagnetic material is a linear relative movement or a curved relative movement.
6. The motional Barkhausen noise stress measurement device according to claim 3, wherein said device body is located on a surface of a ferromagnetic material.
7. The ambulatory Barkhausen noise stress-measuring device of claim 3, wherein the ferromagnetic material either passes through the device body.
8. The device for measuring dynamic barkhausen noise stress according to claim 3, wherein the dynamic barkhausen noise signal pickup unit is a magnetic sensor.
9. The motional Barkhausen noise stress measurement device according to claim 3, wherein the magnetic field guiding unit has a relative permeability > 1.
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| CN202110978575.0A CN113670483A (en) | 2021-08-25 | 2021-08-25 | Method and device for measuring dynamic Barkhausen noise stress |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115031876A (en) * | 2022-05-10 | 2022-09-09 | 南京工业大学 | Square wave excitation-based Barkhausen effect stress detection method |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN115031876A (en) * | 2022-05-10 | 2022-09-09 | 南京工业大学 | Square wave excitation-based Barkhausen effect stress detection method |
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