SU896561A1

SU896561A1 - Method of non-destructive inspection of electroconducting objects

Info

Publication number: SU896561A1
Application number: SU802908849A
Authority: SU
Inventors: Валерий Федорович Змитрук; Виктор Леонидович Сорокин
Original assignee: Центральный научно-исследовательский институт черной металлургии им.И.П.Бардина
Priority date: 1980-03-18
Filing date: 1980-03-18
Publication date: 1982-01-07

Description

() СПОСОБ НЕ РАЗРУШАЮЩЕ ГО КОНТРОЛЯ ЭЛЕКТРОПРОВОДЯЩИХ ОБЪЕКТОВ() METHOD WITHOUT DESTRUCTURING THE CONTROL OF ELECTRIC CONDUCTING OBJECTS

II

Изобретение относитс к неразрушающему контролю материалов и изделий и может быть использовано дл контрол качества электропровод щих объектов.The invention relates to non-destructive testing of materials and products and can be used to control the quality of electrically conductive objects.

Известен способ неразрушающего контрол электропровод щих объектов, заключающийс в том, что пропускают через объект контрол электрический ток, регистрируют магнитное поле рассе ни , возникающее в области дефекта , с помощью магнитного порошка и визуального осмотра поверхности объекта контрол ПНедостатками этого способа вл ютс трудоемкость процесса контрол и наличие субъективных факторов в оценке результатов контрол .There is a method of non-destructive testing of electrically conductive objects, which consists in passing an electric current through the test object, registering the stray magnetic field occurring in the defect area, using a magnetic powder and visual inspection of the surface of the test object. The disadvantages of this process are the presence of subjective factors in evaluating the results of the control.

Наиболее близким по технической сущности к изобретению вл етс способ неразрушающего контрол электро провод щих объектов, заключающийс в том, что возбуждают в объекте электрическое и магнитное пол и регистрируют акустические сигналы Г22.The closest in technical essence to the invention is a method of non-destructive testing of electrically conducting objects, which consists in exciting an electric and magnetic field in an object and recording acoustic signals G22.

Недостатками этого способа вл ютс невысока чувствительность, св занна с низким коэффициентом передачи преобразователей акустических сигналов в электрические, и низка производительность, обусловленна локальностью контрол .The disadvantages of this method are low sensitivity due to the low transmission coefficient of the transducers of acoustic signals into electrical ones, and low productivity due to locality of control.

Цель изобретени - повышение чувствительности и производительности The purpose of the invention is to increase the sensitivity and performance.

10 контрол .10 control.

Эта цель достигаетс за счет того , что создают двухкомпонентное электрическое поле, состо щее из посто нной и импульсной компонент.This goal is achieved by creating a two-component electric field consisting of a constant and a pulsed component.

tsts

(фоме того, возбуждают посто нную компоненту электрического пол , а импульсную компоненту накладывают на нее.(In addition, they excite a constant component of the electric field, and impulse component is superimposed on it.

Claims

In order to increase the sensitivity of the control by detuning from the influence of the magnetic inhomogeneity of the material of the object of control, the value of the constant 3 components of the electric field is sufficiently set for the magnetic saturation of the material. The method is as follows. A constant electric field is excited in the object, and a magnetic field arises in the object, the lines of which are closed around the object And are orthogonal to the direction of the direct current, which excites the electric field. A pulsed electric field is excited in the object (a pulsed current is passed), while it is distributed over the surface of the object due to the surface effect. As a result of a pulsed electric field with a magnetic field, mechanical compressive or tensile Lorentz forces acting on the surface normal will act on the surface of the object. These forces are distributed over the entire surface of the object evenly along its length. In the presence of a surface crack, due to the leakage of a portion of the pulsed current beneath it, local mechanical forces are applied to the crack banks and directed along the object. These forces are of a local and dynamic nature, which leads to the appearance of an elastic wave, which is recorded by a receiver mounted on the object. The high sensitivity of the method is ensured by the fact that the maximum of the acoustic pressure of the elastic wave coincides with the direction of the force exciting this wave, and the productivity is due to the fact that during control the scanning operation is canceled. Claim 1. A method of non-destructive testing of electrically conductive objects, including excitation of an electric field in an object and recording of acoustic signals, different teM, which, in order to increase the sensitivity and performance of the control, create a two-component electric field consisting of a constant and a pulsed component. 2. A method according to claim 1, characterized in that it excites a constant component of the electric field, and impulse component is superimposed on it. 3 .. The method according to claim 1, characterized in that, in order to increase the sensitivity of the control by detuning from the influence of the magnetic inhomogeneity of the material of the test object, the value of the permanent component of the electric field is sufficient for magnetic saturation of the material. Sources of information taken into account in the examination 1. Non-destructive testing of metals and products. Directory. Ed. G. S. Samoylovich. M., Mechanical Engineering, 1976, p. 156.

2. Devices of nondestructive control of materials and products. Directory. Ed. V. V. Klyuev, vol. 2, M., Mechanical Engineering, 1976, p. 197 - 199 (prototype).