SU855568A1 - Method of ferromagnetic material quality determination - Google Patents

Description

I

The invention relates to a technique of magnetic measurements and can be used in the radio engineering, engineering, aviation, industry, as well as in the communications industry for express control of the quality characteristics of ferromagnetic materials.

A known method for determining the quality of ferromagnetic mariashes is based on the interaction of the field of the sample being measured with the auxiliary current field. The devices implementing this method use a magnetoelectric measuring mechanism, for which the pointer deflection is proportional to the product of the current in the winding of the frame by the magnetic $ 1 induction in the air gap

I have enough of this method to have low accuracy and sensitivity, the need to make samples of certain sizes, as well as relatively large sizes of the transducer.

The closest in technical essence to the present invention is a method for determining ferromagnetic materials, implemented in an optical magnetometer. The way is

in the interaction of the field of the sample being measured, placed on a mobile (swing) system, with the field of a magnet. According to the degree of response of the mobile system, to the result of the interaction of the indicated fields, the quality of the ferromagnetic material is judged 23.

The disadvantages of this method are low accuracy and sensitivity of measurements, narrow functionality and implementation complexity.

The purpose of the invention is to improve the measurement accuracy.

15

The goal is achieved by the fact that in the method of determining the quality of ferromagnetic materials, including determining the result of the interaction of the field of the sample under study, fixed on the moving system, with an auxiliary current field, the sample is subjected to free oscillations without deforming it, the logarithmic decrement and oscillation period are determined, then in the zone of oscillations of the sample, a given electromagnetic field is created, at which the logarithmic decrement and period of oscillations are redefined and by the difference of their values electromagnetic presence

the floor and in its absence determine the quality of the ferromagnetic material.

The drawing shows a block diagram of a device that implements the proposed method.

The device contains an oscillatory system that includes an elastic torsion 1, an inertial disk 2, a centering unit 3, sample 4, a rod 5 for attaching the sample, coil b with core 7, into the gap of which sample 4 enters, a phototransducer including light source 8, optical shutter 9 attached to the disk 2, the photodetector 16, gauges of the logarithmic decimal 11 and the oscillation period 12.

The method is carried out as follows.

Sample 4. is firmly fixed on the stem 5 of a nonmagnetic material. After removing the additional torque, the oscillatory system, consisting of the torsion bar 1, one end of which is rigidly fixed in the clamping bar and the second in the clamp of the inertial disk 2, makes free, exponentially damped oscillations. In this case, sample 4 oscillates in the gap of an electromagnet consisting of coil b with core 7. Electrical oscillations from the output of the photodetector 10 are fed to the meters of the logarithmic decrement 11 and the oscillation period 12.

First, the parameters of free oscillations in the absence of an electromagnetic field are measured, i.e. without voltage and, and then with voltage and. The difference in the measurement, determined by the qualitative characteristics of the sample (magnetization, anisotropy constant, mechanical and magnetic state), is proportional to the value of C ,.

Claims (2)

1. Preobrazhensky A.A. Magnetic materials and elements. Higher School, M., 1976, p. 231. 2. USSR author's certificate number 157413 Cl. G 01 R 33/12, 1962.