SU849056A1 - Method of electromagnetic structuroscopy of ferromagnetic bodies of revolution - Google Patents

Description

one

The invention relates to non-destructive testing and can be used to control the structure of its inhomogeneities and the physicomechanical properties of steel and cast-iron parts, having the form of rotation bodies.

The known method of structuroscopy of ferromagnetic materials consists in the fact that the product is affected by rotating and constant magnetic fields and the spectrum of the EMF of the converter located near the controlled product is judged by its properties flj.

The drawbacks of the known method are the impossibility of determining the structure of the whole product and the complexity of its implementation,

The closest to the proposed technical essence is the method of electromagnetic structuroscopy, which consists in the fact that a monitored product is briefly affected by a constant magnetic field and, according to the parameters of the residual magnetization field, its properties are C2,

The disadvantages of this method are the small information content of the control and the complexity in the control of products with rotation bodies.

The purpose of the invention is to simplify and increase the information content of the control.

ten

The goal is achieved in that the magnetization of the product is carried out in a direction perpendicular to the axis. rotation, rotate the product around this axis, and about controlled parameters are judged by the EMF spectrum of the converter installed near the product being monitored.

FIG. I shows the magnetization scheme of the controlled product; on

Claims (2)

20 of FIG. 2 — a picture of the residual magnetization field of a product with a uniform structure; in fig. 3 - the same for a product with a non-uniform structure; Fig. 4 shows the form of the NDS converter for products with a uniform and non-uniform structure, respectively. The electromagnetic structure scoop method is carried out as follows. The controlled product 1 is briefly affected by the constant magnetic field of the electromagnet 2 in the direction perpendicular to the axis of rotation of the product. Then, the product is rotated around this axis and the EMF spectrum of the transducer 3 installed near the surface of the rotating product is analyzed. If the product has a homogeneous structure (Fig. 2), then the EMF of the converter is symmetrical about the abscissa axis (Fig. 4a) and contains only odd harmonics. In this case, the effective value of the EMF and its harmonic composition is determined by the strength of the residual magnetization field and its form. These field parameters determine the mechanical properties of the controlled product. If the product has structural heterogeneity (Fig. 3), then the form of the EMF of the converter is asymmetric (Fig. 4b). In this case, a constant component and even harmonics of MONICA appear in the EMF spectrum of the converter, the magnitude of which depends on the size and shape of the heterogeneity. The proposed method is simple to implement and provides control of many parameters of ferromagnetic bodies of revolution. The invention The method of electromagnetic structuroscopy of ferromagnetic bodies of revolution, which consists in the fact that a controlled product is briefly affected by a constant magnetic field and, according to the parameters of the residual magnetization field, is judged by its properties, the magnetization is produced in the direction perpendicular to the axis of rotation, the product is rotated around this axis, and about the controlled parameters are judged by the EMF spectrum of the converter, it is established go near the monitored product. Sources of information taken into account in the examination 1. The author's certificate of the USSR 533860; CL, G 01 N 27/86, 1971. 2. Inconsistent control of metals and products. Handbook ed. G.S. Samoilovich, M., Mechanical Engineering, 1976, p. 196 (prototype).