RU2559118C1 - Method for determining parameters of dynamic deformation of metallic materials and device for its implementation - Google Patents

Abstract

FIELD: measurement equipment.

SUBSTANCE: at recording of an electromagnetic field occurring at dynamic deformation of bodies, a useful signal is recorded by using the investigated specimen connected through a coaxial connection to the measuring device. The investigated specimen is the primary physical converter of impact action to a useful signal.

EFFECT: providing a possibility of direct measurement without any high instrument and statistical errors.

2 cl, 4 dwg

Description

The invention relates to devices for determining the parameters of high-speed movement of propelling bodies, for example, measuring overloads, collision speeds, etc., and can be used to study the parameters of the dynamic deformation of metallic materials in aviation and space technology.

A device is known that allows one to determine the parameters of body motion in a medium, using X-ray speed photography, which allows judging by the results of decoding frames to judge the geometric and power parameters of body motion in a medium [1].

The device [2] uses a piezoelectric transducer mounted on a movable body, a transmitting antenna and a telemetry system for receiving and recording the output signal, an overload or pressure sensor of a generating type is installed on the movable body, which additionally contains a coil electrically connected, for example, to the piezoelectric element and placed on the surface of a moving body. The device [2] operates as follows. If pressure acts on the moving body at the location of the sensor, then a charge arises of corresponding magnitude, which causes a current in the coil electrically connected to it. This current is accompanied by electromagnetic radiation of the coil, the intensity of which and the nature of the changes judge the pressure parameters acting on the sensor. Electromagnetic radiation is perceived by the antenna and can be detected after conversion.

A known method [3] of controlling the crushing of materials, including the registration of electromagnetic radiation arising from the dynamic destruction of materials. The electromagnetic radiation generated by the crushed mass causes the appearance of electrical signals in the loop antennas tuned to different frequencies. By comparing the signal spectra obtained during operation with the reference ones, a deviation in the spectral characteristics of the signals is revealed, which is used to judge deviations in the process of grinding the material.

The closest in technical essence to the proposed method is the method specified in [4]. The paper presents the results of experimental studies of electromagnetic phenomena accompanying the rapid deformation of various materials. It is shown that the fast-flowing deformation of various substances, both shock and quasistatic, is accompanied by electromagnetic radiation generated by the deformed substance itself. It is noted that the temporal parameters of the recorded electromagnetic radiation signal are correlated with the temporal parameters of the mechanical deformation process. The experimental setup scheme [4] includes: a target, a pneumatic throwing installation, an antenna for detecting electromagnetic radiation.

A common drawback of the above technical solutions is the need to include in the composition of the devices an antenna that detects electromagnetic radiation, which is a secondary physical field. Thus, the considered technical solutions are indirect methods of measurement, which are characterized by large instrumental and statistical measurement errors.

The difference of the proposed method lies in the absence of a recording antenna, since the source of the useful signal in the measurement circuit is the test sample itself.

The proposed device operates as follows. As a result of the impact interaction of the projectile with the target, the spatial redistribution of charges (i.e., electromotive force) occurs in the latter, which is then registered by the proposed device, the circuit of which is shown in FIG. 1. The test sample 1 has an electrical coaxial connection 2 with a measuring device 3. As an measuring device 3, an oscilloscope, voltmeter, or the like can be used. The composition of the coaxial compound 2 includes a capacitor 4.

T.O. the target itself or the object of study is the primary physical converter of the impact into a useful signal. It should be noted that the present invention can only be used in the study of metallic materials and structures.

In order to confirm the technical feasibility of the proposed method and device, the team of authors conducted experimental studies, the scheme of which is presented in FIG. 2. Drummer 6 was accelerated by the pneumatic accelerator 5. At the moment of the impactor 6 departure from the barrel of the accelerator 5, the contactor 7 was driven by compressed air. Measuring device 3 (oscilloscope) recorded two signals: from the current source 9 and target 1. The waveforms are shown in FIG. 3 in the case of hit by a striker in the target, and FIG. 4 - in case of a miss.

Literature

1. 1. Physics of high-speed processes. Collection of articles, ed. Zlatina - M.: Mir, p. 74.

2. Yu.K. Bivin, V.V. Viktorov, Yu.V. Kulinich, A.S. Chursin. Overload meter Copyright certificate No. 794547. Date of publication of the description 07.01.81. Institute of Mechanics Problems, Academy of Sciences of the USSR.

3. S.N. Rodak, V.I. Fox, S.N. Grinko, N.I. The ball. A method of controlling crushing of materials. Copyright certificate No. 1208496. Date of publication of the description 07/30/89. Institute of Geotechnical Mechanics, Academy of Sciences of the Ukrainian SSR.

4. Bivin Yu.K., Viktorov V.V., Kulinich Yu.V., Chursin A.S. Electromagnetic radiation during the dynamic deformation of various materials. Solid Mechanics, No. 1, 1982. Publishing House "Science". S. 183-186.

Claims (2)

1. The method of determining the parameters of the dynamic deformation of metallic materials, which consists in registering an electromagnetic field arising from the dynamic deformation of bodies, characterized in that the useful signal is recorded using the test sample connected through a coaxial connection to the measuring device, while the test sample is primary physical transducer of shock into a useful signal. 2. A device for implementing the method according to claim 1, comprising a test sample, a coaxial connection, a measurement device, a capacitor, characterized in that the test sample is connected through a coaxial connection to the measurement device, wherein the test sample is the primary physical transformer of impact into a useful signal .

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