Amorphous wire axial hysteresis loop measuring device

Abstract

The invention discloses an amorphous wire axial hysteresis loop measuring device, which relates to the technical field of magnetic performance testing and comprises an axial magnetic field generating device, a current sampling resistor, a differential amplifier, an integrating circuit, an oscilloscope and an induction coil. The axial magnetic field generating device comprises a magnetism generating coil, and when current is introduced into the magnetism generating coil, an axial magnetic field is generated; the current sampling resistor is connected in series with the magnetism-generating coil; two ends of the current sampling resistor are connected with a first channel of the oscilloscope; the axial direction of the induction coil is parallel to the axial magnetic field, the induction coil is arranged in the center of the magnetism generation coil, and the two ends of the induction coil are connected to the input end of the differential amplifier; the output end of the differential amplifier is connected with the input end of the integrating circuit, and the output end of the integrating circuit is connected with a second channel of the oscilloscope; the invention provides a novel method for measuring the axial hysteresis loop of the amorphous wire.

Description

Technical Field

[0001] The present application relates to the field of magnetic property testing, in particular to the technical field of magnetic property testing of magnetically sensitive materials, and in particular to a device for measuring the axial hysteresis loop of an amorphous wire. Background Art

[0002] Amorphous wire has gained wide attention and research in the field of magnetic sensor applications due to its unique giant magneto-impedance effect. Sensors made of amorphous wire as sensitive material have the characteristics of high sensitivity, fast response speed, high linearity, and good temperature stability. It was first discovered in Co-based alloys by Japanese scholars Mohri.K et al. in 1992 using the inner circle water spinning method. The impedance change rate of the prepared Co-based amorphous wire can reach 300%, which is 1-2 orders of magnitude higher than the characteristics of sensitive materials used in traditional GMR sensors.

[0003] However, due to the amorphous characteristics of amorphous wires and the large residual stress introduced by the ultra-high cooling rate during the preparation of amorphous wires, amorphous wires generally need to be tested for their performance parameters to ensure that they perform normally. Among them, the axial hysteresis loop is one of the important performance parameters. However, due to the small size of amorphous wires, it is impossible to measure them using traditional methods. Summary of the invention

[0004] The purpose of the present application is to provide a device for measuring the axial hysteresis loop of an amorphous wire, so as to solve the problem of difficulty in measuring the axial hysteresis loop of an amorphous wire described in the background art.

[0005] To achieve the above-mentioned purpose, the present application provides an amorphous wire axial hysteresis loop measuring device, comprising: an axial magnetic field generating device, a current sampling resistor, a differential amplifier, an integrating circuit, an oscilloscope, an induction coil and a computer device;

[0006] The axial magnetic field generating device comprises a magnetoelastic coil, and when a current flows into the magnetoelastic coil, an axial magnetic field is generated;

[0007] The current sampling resistor is connected in series with the magnetic coil and is used to sample the current of the magnetic coil;

[0008] Two ends of the current sampling resistor are connected to the first channel of the oscilloscope;

[0009] The communication port of the oscilloscope is connected to the computer device, the induction coil is placed parallel to the axial magnetic field, and both ends of the induction coil are connected to the input end of the differential amplifier;

[0010] The output end of the differential amplifier is connected to the input end of the integration circuit, and the output end of the integration circuit is connected to the second channel of the oscilloscope;

[0011] Optionally, the axial magnetic field generating device further includes a function generator and a power amplifier, the output end of the function generator is connected to the input end of the power amplifier, and the output end of the power amplifier is connected to the magnetic generating coil.

[0012] Optionally, the function generator is a sine function generator.

[0013] Optionally, the magnetic coil is a Helmholtz coil or a solenoid, and the induction coil is placed between the Helmholtz coils; the power amplifier, the Helmholtz coil or the solenoid and the current sampling resistor form a series loop.

[0014] Optionally, the induction coil includes a first induction coil and a second induction coil with the same coil parameters, the first induction coil and the second induction coil are connected at the same end, and the other two ends are connected to two input ends of the differential amplifier.

[0015] Optionally, the coil parameters include a coil cross section and a coil turn number.

[0016] Optionally, the device further comprises a printed circuit board, and the induction coil is soldered on the printed circuit board.

[0017] The amorphous wire axial hysteresis loop measuring device provided in the embodiment of the present application includes an axial magnetic field generating device, a current sampling resistor, a differential amplifier, an integrating circuit, an oscilloscope and an induction coil. The axial magnetic field generating device generates an axial magnetic field, and the current of the magnetic coil generating the axial magnetic field is sampled by the current sampling resistor and sent to the first channel of the oscilloscope, so that the sampled current is collected by the oscilloscope, thereby calculating the magnetic field strength.

[0018] The induction coil is placed parallel to the axial magnetic field. There is an amorphous wire with high magnetic permeability in the induction coil. The induction coil generates an induced voltage in the sinusoidally changing axial magnetic field, which is then sent to the second channel of the oscilloscope through a differential amplifier and an integrating circuit in sequence; the magnetic induction intensity is calculated accordingly. The axial magnetic field is slowly increased from zero to saturate the amorphous wire. The oscilloscope can display the axial hysteresis loop of the amorphous wire in the XY mode. Therefore, the present application provides a new method for measuring the axial hysteresis loop of an amorphous wire. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1A logic diagram of an amorphous wire axial hysteresis loop measurement device provided in one embodiment of the present application;

[0021] Figure 2 A schematic diagram of a device for measuring an axial hysteresis loop of an amorphous wire provided in another embodiment of the present application;

[0022] Figure 3 A schematic diagram of an axial hysteresis loop of an amorphous wire provided in yet another embodiment of the present application. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0024] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0025] In an exemplary embodiment, Figure 1 As shown, a device for measuring the axial hysteresis loop of an amorphous wire is provided, and the device comprises an axial magnetic field generating device, a current sampling resistor R, a differential amplifier, an integrating circuit, an oscilloscope, an induction coil and a computer device.

[0026] The axial magnetic field generating device comprises a magnetoelastic coil. When current flows into the magnetoelastic coil, an axial magnetic field is generated. The sinusoidally varying current generates a sinusoidally varying magnetic field.

[0027] The current sampling resistor R is connected in series with the magnetic generating coil and is used to sample the current of the magnetic generating coil.

[0028] The two ends of the current sampling resistor R are connected to the first channel of the oscilloscope, so that the oscilloscope collects the current of the magnetic coil.

[0029] The communication port of the oscilloscope is connected to the computer device, so that the computer device determines the magnetic field strength of the axial magnetic field according to the current of the magnetizing coil.

[0030] The induction coil is placed horizontally in the axial magnetic field, and two ends of the induction coil are connected to two input ends of the differential amplifier.

[0031] The output end of the differential amplifier is connected to the input end of the integration circuit, and the output end of the integration circuit is connected to the second channel of the oscilloscope, so that the oscilloscope collects the induced voltage.

[0032] The communication port of the oscilloscope is connected to the computer device, so as to determine the magnetic induction intensity B of the amorphous wire 11 to be detected according to the induced voltage.

[0033] The axial magnetic field may be understood as an axial magnetic field with the amorphous wire 11 as a reference.

[0034] The axial magnetic field generating device passes current into the magnetic generating coil so that the magnetic generating coil generates an axial magnetic field, thereby creating conditions for measuring the axial hysteresis loop of the amorphous wire 11 .

[0035] Among them, the differential amplifier is also called an instrument amplifier, which includes two input terminals, each of which is connected to one end of the induction coil, and amplifies the input induced voltage to obtain an amplified voltage.

[0036] The use process of the above-mentioned amorphous wire axial hysteresis loop measurement device is as follows:

[0037] Connect the axial magnetic field generating device, the current sampling resistor R, the differential amplifier, the integrating circuit, the oscilloscope, the induction coil and the computer equipment according to the above connection relationship;

[0038] Passing current into the magnetic coil so that the magnetic coil generates an axial magnetic field;

[0039] The induction coil is placed parallel to the axial magnetic field, so that the axial direction of the induction coil is consistent with the magnetic field direction of the axial magnetic field;

[0040] The amorphous wire 11 to be measured is inserted into the induction coil. After insertion, the axial direction of the amorphous wire 11 is consistent with the axial direction of the induction coil. At this time, the axial magnetic field generated by the magnetic coil is also consistent with the axial direction of the amorphous wire 11, that is, the axial magnetic field of the amorphous wire 11 is formed;

[0041] At this time, the induction coil generates an induced voltage in the sinusoidally changing axial magnetic field, and the induced voltage is connected to the differential amplifier, which amplifies the induced voltage to obtain an amplified voltage, and then sends the amplified voltage to the integration circuit, oscilloscope, and computer equipment in sequence;

[0042] At the same time, the oscilloscope obtains the current of the magnetizing coil through the current sampling resistor R, and converts the current into the magnitude of the axial magnetic field;

[0043] The oscilloscope sends the voltage signal to the computer device;

[0044] After receiving the voltage signal, the computer device calculates the magnetic induction intensity B corresponding to the voltage output by the integration circuit and the magnetic field intensity H corresponding to the magnetic coil according to the voltage signal, and displays them in XY mode to obtain the axial hysteresis loop of the amorphous wire 11.

[0045] Alternatively, see Figure 2 The axial magnetic field generating device also includes a function generator and a power amplifier, the output end of the function generator is connected to the input end of the power amplifier, and the output end of the power amplifier is connected to the magnetic coil.

[0046] Among them, the function generator is used as an excitation source and sent to the power amplifier.

[0047] The power amplifier amplifies the power and sends it to the magnetizing coil, which generates an axial magnetic field.

[0048] Optionally, the function generator is a sine function generator.

[0049] The sine function generator is a common function generator and is easy for staff to operate.

[0050] Alternatively, see Figure 2 The magnetic coil is a Helmholtz coil, which includes two sub-coils, which are respectively denoted as a first sub-coil 10 and a second sub-coil 20. The induction coil is placed at the center between the first sub-coil 10 and the second sub-coil 20; the power amplifier, the first sub-coil 10, the second sub-coil 20 and the current sampling resistor R form a series circuit.

[0051] Optionally, the magnetic coil may also be a solenoid.

[0052] The induction coil is axially parallel to the axial direction of the Helmholtz or solenoid and is placed at a central position so that the induction coil and the amorphous wire to be measured are in a uniform magnetic field.

[0053] In addition, when performing measurements, the axial magnetic field generated by the Helmholtz coil is aligned with the east-west direction in order to reduce the influence of the geomagnetic field on the axial magnetic field.

[0054] In addition, the method of using the Helmholtz coil can be found in the relevant prior art, and this application will not elaborate on it here.

[0055] Alternatively, see Figure 2 The induction coil includes a first induction coil Lp and a second induction coil Lc with the same coil parameters. The first induction coil Lp and the second induction coil Lc are connected at the same end, and the other two ends are connected to the two input ends of the differential amplifier.

[0056] When two induction coils are provided, the amorphous wire 11 passes through the first induction coil Lp.

[0057] Optionally, the coil parameters include coil cross section, coil turns, etc.

[0058] The coil cross section and the number of coil turns are the parameters that determine the basic performance of the coil, so it is necessary to ensure that these parameters of the two induction coils are the same.

[0059] Optionally, the device for measuring the axial hysteresis loop of the amorphous wire 11 further includes a printed circuit board, and the induction coil is welded on the printed circuit board.

[0060] The printed circuit board (full name in English: Printed Circuit Board; English abbreviation: PCB) is used to fix the induction coil and improve the measurement accuracy.

[0061] Optionally, the device for measuring the axial hysteresis loop of the amorphous wire 11 further includes a display terminal, and the display device is connected to the computer device.

[0062] The computer device displays the calculated magnetic field intensity H and magnetic induction intensity B through the display terminal, so that the staff can intuitively see the axial hysteresis loop of the amorphous wire 11. Figure 3 shown.

[0063] In addition to being able to observe the axial hysteresis loop of the amorphous wire 11 in XY mode, the oscilloscope also has the function of measuring the axial hysteresis loop, such as measuring the coercive force, saturation magnetic field intensity, remanence and saturation magnetic induction intensity.

[0064] The coercive force HC of the axial hysteresis loop of the amorphous wire 11 is HC=K·I=K·(U1 / R), where R is the current sampling resistor R, U1 is the voltage of the first channel of the oscilloscope, and K is the conversion coefficient between the magnetic field and the current.

[0065] This application uses common instruments and equipment to observe the axial hysteresis loop of the amorphous wire 11, and to measure the coercive force, saturation magnetic field intensity, remanence and saturation magnetic induction intensity, and also provides valuable key information for the design of magnetic sensors.

[0066] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, 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.

[0067] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A device for measuring the axial hysteresis loop of an amorphous wire, characterized in that: include: An axial magnetic field generating device, a current sampling resistor, a differential amplifier, an integrating circuit, an oscilloscope and an induction coil; The axial magnetic field generating device comprises a magnetoelastic coil, and when a current flows into the magnetoelastic coil, an axial magnetic field is generated; The current sampling resistor is connected in series with the magnetic coil and is used to sample the current of the magnetic coil; Two ends of the current sampling resistor are connected to the first channel of the oscilloscope; The induction coil is placed in parallel to the center of the axial magnetic field, and the axial direction of the induction coil is parallel to the axial magnetic field, and both ends of the induction coil are connected to the input end of the differential amplifier; The output end of the differential amplifier is connected to the input end of the integration circuit, and the output end of the integration circuit is connected to the second channel of the oscilloscope.

2. The amorphous wire axial hysteresis loop measuring device according to claim 1, characterized in that: The axial magnetic field generating device further comprises a function generator and a power amplifier, wherein the output end of the function generator is connected to the input end of the power amplifier, and the output end of the power amplifier is connected to the magnetic generating coil.

3. The amorphous wire axial hysteresis loop measuring device according to claim 2, characterized in that: The function generator is a sine function generator.

4. The amorphous wire axial hysteresis loop measuring device according to claim 2, characterized in that: The magnetic coil is a Helmholtz coil or a solenoid; the power amplifier, the Helmholtz coil or the solenoid, and the current sampling resistor form a series loop.

5. The amorphous wire axial hysteresis loop measuring device according to claim 1, characterized in that: The induction coil comprises a first induction coil and a second induction coil with the same coil parameters. The first induction coil and the second induction coil are connected at the same end, and the other two ends are connected to the two input ends of the differential amplifier.

6. The amorphous wire axial hysteresis loop measuring device according to claim 5, characterized in that: The coil parameters include coil cross section and coil turns.

7. The amorphous wire axial hysteresis loop measuring device according to claim 1, characterized in that: The amorphous wire axial hysteresis loop measuring device also includes a computer device, and the computer device is connected to the communication port of the oscilloscope.

8. The amorphous wire axial hysteresis loop measuring device according to any one of claims 1 to 7, characterized in that: The device also includes a printed circuit board, and the induction coil is soldered on the printed circuit board.

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