SU892387A1 - Device for measuring ferromagnetic material parameters - Google Patents

Description

one

The invention relates to a magnetic measuring technique and is intended to study the parameters of Barkhausen noise in local areas of ferromagnetic materials under complex regimes of their magnetization reversal.

Of the known devices of similar purpose, the closest to the technical essence of the invention is a converter containing a U-shaped magnetizing magnetic circuit with a magnetizing winding connected through a power amplifier to a linear slow-current source and a magnetic induction sensor located on the surface of the material under study.

However, the measurement of Barkhausen tum parameters at different points in the hysteresis loop is made with unequal changes in induction in the material, which makes it difficult to compare the results. For example, when a ferromagnet is simultaneously affected by a quasistatic (slowly varying linearly) field H and a high-frequency sinusoidal field H 0, the amplitude due to the change in induction at (different points of the hysteresis loop will not be equal

at constant amplitude of change

external sine wave AND

0

those. d etc. at dN.1 dNg | dnz Since the amplitude of the change in induction at the point of the hysteresis loop is different, then compare the parameter; The Barkhausen noise obtained in ka: by a food at a loop point under this mode of magnetization reversal is impossible.

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The purpose of the invention is to increase reliability.

The goal is achieved by the fact that a device for measuring parameters of ferromagnetic materials containing a U-shaped magnetizing Magnetowire with a magnetizing winding connected through a power amplifier to a linear mediocrementocurrent source, and a magnetic inductive, is connected to a tem- pered pattern, which will be connected to a tem- inal pattern. Two additional windings are applied, applied to the magnetizing magnetic core, and series-connected current regulator, a source of controlled sinusoidal current and a power amplifier connected to one of the pins, and the regulator input

30 current is connected to another winding.

Claims (1)

4 Figure 1 shows a block diagram of the device. Fig. 2 is a diagram of its mode of operation at certain points in time, corresponding to different points of the hysteresis loop. The device (Fig. 1) contains П-ο different magnetizing magnetic circuit 1, on which a magnetizing winding 2 is applied, connected through an amplifier 3 with output source Nick 4 of the linear slow current, the magnetizing winding 5 connected to the output of the source b of the controlled sinusoidal current through the power amplifier 7, the winding 8 connected to the input of the regulator 9 amplitude of the sinusoidal current, output- which is connected to the input of the source 6 of a controlled sinusoidal current, a magnetic induction sensor, which is connected from the U-shaped magnetic circuit 10 with the measuring winding 11 applied to it, the converter operates as follows. The current 3 flowing through the winding 2 creates in magnetic circuit 1 linearly linear magnetic flux F, which closes through the material under study and which can be considered constant during a short time interval. In this case, the magnetic state of the material of the magnetic circuit 1 varies along the corresponding hysteresis loop (Fig. 2). The current (/ flowing through the winding 5) creates a sinusoidally varying magnetic flux Og in the magnetic conductor, which provides a change in the magnetic state of the magnetic circuit material 1 and the material under investigation private cycles at each hysteresis point of the loop, the emf induced in winding 8, consists of two components due to a change in the magnetic fluxes f and fl and is equal to ... where Wi | is the number of turns of the winding 8. Because in a given p In the mode of magnetization reversal, the flux Φ varies slowly (the cycle time of the linear magnetization reversal is 10–100 s), then we can assume that, then, this emf is supplied to the regulator 9 of the amplitude of the sinusoidal current, which regulates the amplitude value of the current 3 according to the law inversely proportional to the differential magnetic permeability (); wherein the amplitude of change of the magnetic flux Φ is a constant value at each point of the hysteresis loop (Fig. 2). The magnetic induction sensor records the Barkhausen noise at constant increments of induction s B in the material at each point of the hysteresis loop. Thus, the use of the proposed converter ensures the comparability of the Barkhausen noise parameters under complex reversal modes. An apparatus for measuring the parameters of ferromagnetic materials, comprising a U-shaped magnetizing magnetic circuit with a magnetizing winding connected through a power amplifier to a linear slow-current source, and an magnetic induction sensor, axisymmetric to the U-shaped magnetizing magnetic circuit, which is a non-woven, axisymmetric, magnetic U-shaped magnetising magnetic circuit that is different from the U-shaped magnetizing magnetic circuit, which is a non-symmetric sensor, which is axially symmetric to the U-shaped magnetizing magnetic circuit, which is a non-woven, axisymmetric sensor, which is a symmetric U-shaped magnetizing magnetic circuit, which is a non-symmetric sensor, which is axially symmetric to the U-shaped magnetizing magnetic circuit, which is a non-symmetric sensor, which is axially symmetric to the U-shaped magnetizing magnetic circuit, which is a non-woven, axially symmetric U-shaped magnetizing magnetic conductor, and an open-ended magnetic induction sensor. , two additional windings are applied to it, applied to the magnetizing magnetic circuit, and the current regulator connected in series, a controlled sinusoidal current point and a power amplifier connected to one of the windings, and a current controller input connected to the other winding. Sources of information taken into account in the examination 1, Piskunov D, K, The study of the possibility of determining the magnetic properties of crystallites of ferromagnetic. Candidate dissertation, Vladimir, 1976, p.63. one}& f-i