An Electromagnetic Ultrasonic and Pulsed Eddy Current Composite Detection Sensor

Abstract

The invention discloses an electromagnetic ultrasonic and pulsed eddy current composite detection sensor. The ultrasonic wave and the eddy current are simultaneously excited by the same excitation source, and two channels are respectively used to receive the electromagnetic ultrasonic signal and the pulsed eddy current signal, so as to realize the detection of the near surface and the test piece. detection of internal defects. Specifically, the electromagnetic ultrasonic system excites a high-frequency and high-power pulse signal and sends it to the electromagnetic ultrasonic coil. The electromagnetic ultrasonic coil generates pulsed eddy current under the drive of the excitation signal, and the pulsed eddy current generates ultrasound under the static magnetic field of the permanent magnet; the pulsed eddy current coil receives After receiving the induced voltage signal from the primary magnetic field of the electromagnetic ultrasonic coil and the secondary magnetic field of the pulsed eddy current in the tested piece, the information about the surface defect of the tested piece is obtained after being collected and processed by the oscilloscope; and the electromagnetic ultrasonic coil receives the ultrasonic echo After the induced voltage signal of the electromagnetic wave is amplified and filtered by the electromagnetic ultrasonic system, the information about the internal and lower surface defects of the tested piece is obtained.

Description

technical field [0001] The invention belongs to the technical field of nondestructive testing, and more specifically relates to an electromagnetic ultrasonic and pulsed eddy current composite detection sensor. Background technique [0002] Nondestructive Testing (NDT) technology refers to the change of physical characteristics of the measured object due to defects or differences in organizational structure without damaging the performance, shape and internal structure of the measured object. The technique of understanding and evaluating the nature, quality, state or internal structure of the measured object. Ultrasonic testing is the most mature testing method used in modern industry, but it needs couplant in the testing process, which is not convenient for practical use, and there are detection blind spots. [0003] Electromagnetic ultrasonic (Electromagnetic Acoustic Transducer, EMAT) detection technology is a new detection technology developed on the basis of traditional...

AI Technical Summary

Problems solved by technology

The problem with this method is that the electromagnetic ultrasound and the eddy current are still excited and received separately, and the two probes are different in spatial position, so it is impossible to realize real-time detection of the same position.

Images