SU949486A1

SU949486A1 - Method of checking residual stresses in non-magnetic metal articles

Info

Publication number: SU949486A1
Application number: SU803211313A
Authority: SU
Inventors: Юрий Иванович Стеблев; Наиля Мерзажановна Шехмаметьева; Владлен Александрович Денисов
Original assignee: Куйбышевский Ордена Трудового Красного Знамени Авиационный Институт Им.Акад.С.П.Королева
Priority date: 1980-12-03
Filing date: 1980-12-03
Publication date: 1982-08-07

Description

;54) СПОСОБ КОНТРОЛЯ ОСТАТОЧНЫХ НАПРЯЖЕНИЙ В НЕМАГНИТНЫХ МЕТАЛЛИЧЕСКИХ ИЗДЕЛИЯХ; 54) METHOD FOR MONITORING RESIDUAL VOLTAGES IN NON-MAGNETIC METAL PRODUCTS

Изобретение относитс к неразрушающему контролю и может быть использовано дл определени характера остаточных напр жений.The invention relates to non-destructive testing and can be used to determine the nature of residual stresses.

Известен способ электромагнитного контрол механических напр жений методом высших гармоник, заключающийс в том, что измер ют амплитуду высших гармоник тока электромагнитного преобразовател , по которым суд т о результатах контрол 1.The known method of electromagnetic control of mechanical stresses by the method of higher harmonics, which consists in measuring the amplitude of the higher harmonics of the current of the electromagnetic converter, according to which the results of the control 1 are judged.

Однако способ обладает недостаточной точностью и невозможно определить характер остаточных напр жений .However, the method has insufficient accuracy and it is impossible to determine the nature of residual stresses.

Наиболее близким к изобретению вл етс способ контрол остаточных напр жений в немагнитных металлических издели х, заключающийс в том, что в изделии с помощью установленного на нем линейно-прот женного индуктивного электромагнитного преобразовател возбуждают вихревые токи и определ ют величину ЭДС, наводимой в измерительной обмотке преобразовател , и по величине ЭДС определ ют наличие остаточных механических напр жений 2.The closest to the invention is a method of monitoring residual stresses in non-magnetic metal products, which consists in that the product excites eddy currents by means of a linearly extended inductive electromagnetic converter installed on it and determines the value of the emf induced in the measuring winding of the converter , and the magnitude of the EMF determines the presence of residual mechanical stresses 2.

. Недостатками способа вл ютс невозможность определени характера. The disadvantages of the method are the inability to determine the nature

остаточных напр жений (раст жение или сжатие) и недостаточна точность измерений.residual stresses (tensile or compression) and measurement accuracy is insufficient.

Цель изобретени - определение характера остаточных напр жений и повышение точности измерений.The purpose of the invention is to determine the nature of residual stresses and increase the accuracy of measurements.

Поставленна цель достигаетс тем, что согласно способу контрол остаточных напр жений в немагнитных The goal is achieved by the fact that according to the method of controlling residual stresses in non-magnetic

10 металлических издели х заключающемус в том, что в изделии с помощью установленного на нем линейно-прот женного индуктивного электромагнитного преобразовател возбуждают 10 metal products comprising the fact that the product is excited by means of a linearly extended inductive electromagnetic converter mounted on it

15 вихревые токи и определ ют величину ЭДС, наводимой в измерительной обмотке преобразовател , преобразователь предварительно устанавливают на эталонный образец при отсутствии 15 eddy currents and determine the value of the emf induced in the measuring winding of the converter; the converter is preliminarily mounted on the reference sample in the absence of

20 механической нагрузки и производ т компенсацию ЭДС, наводимой в измерительной обмотке преобразовател до уровн , превышающего величину вносимого напр жени , обусловленно25 го действием на образец максимальной механической нагрузки, ЭДС,наводимую в измерительной обмотке преобразовател при установке его на контролируемое изделие, определ ют 20 of the mechanical load and compensation of the emf induced in the measuring winding of the converter to a level exceeding the magnitude of the applied voltage caused by the effect of the maximum mechanical load on the sample, the emf induced in the measuring winding of the converter when installed on the product under test

Claims

30, with alternating orientation of the converter in the direction coinciding with the direction of the effect of residual stresses and in the direction perpendicular to it, and the magnitude of the ratio of the measured emf determine the nature of the residual stresses. The method is implemented as follows. A linearly extended inductive electromagnetic transducer is installed on a reference image without residual mechanical stresses, and it induces eddy currents in it, the emf induced in the measuring winding of the transducer is compensated to the level Uo where UQ is the magnitude of the applied voltage caused by the action sample maximum mechanical load. Then, the converter is installed on a controlled device in the direction coinciding with the direction of residual voltage, the UnpOA value of the EMF induced in the measuring winding of the converter is measured, the converter is installed in the direction perpendicular to the direction of the residual voltage action, and the Ziper value is measured EMF induced in the measuring winding of the converter. The nature of the residual stresses is determined from the conditions of the DLC, 1 - the nature of the stress, .prol 1 - the nature and the forward stresses - compression / The invention can be used to control the residual stresses in various engineering objects, as it allows accuracy determine the magnitude of the voltages and their nature. Claims The method of controlling residual stresses in non-magnetic metal products is that the product excites eddy currents by means of a linearly extended inductive electromagnetic converter installed on it and determines the value of the emf induced in the measuring winding of the converter, characterized by that, in order to determine the nature of the residual mechanical stresses and improve the measurement accuracy, the transducer is pre-installed on the reference sample with no The mechanical load and compensation of the EMF induced in the measuring winding of the converter to a level exceeding the magnitude of the applied voltage caused by the maximum mechanical load acting on the sample, the EMF induced in the measuring winding of the converter when installed on the product under test, is determined by alternate orientation the converter in the direction coinciding with the direction of the effect of residual stresses, and in the perpendicular direction to it, and according to the value of the ratio These emfs determine the nature of the residual stresses. Sources of information taken into account during the examination 1. USSR author's certificate No. 289352, cl. G 01 N 27/86, 1971.

2. Gorazdovsky T.Ya. and Tatarnikov V.M. Inductive measurement of rheological stresses in non-ferromagnetic metals. - Defectoscopy, 1973, No. 5.