Permanent magnet-free omnidirectional SH wave electromagnetic ultrasonic transducer and design method thereof

Abstract

The invention discloses a permanent magnet-free omnidirectional SH wave electromagnetic ultrasonic transducer and a design method thereof. The transducer comprises two parts of PCB coils and an insulating layer. One part of the PCB coil is an electromagnetic field coil, is of an annular structure, is used for providing a bias electromagnetic field, and is composed of two layers of coils connectedend to end to form a closed loop. The other part of the PCB coil is a coil used for generating eddy current in a board, and two ends of the coil are respectively connected with an external lead. The insulating layer covers the head and tail ends of the PCB coil and is connected with the wire, and the wire is connected with an external power supply. The transducer can control the size of the generated magnetic field to meet the requirements of different detection conditions according to methods of controlling the size of the power-on current and the like. Because no magnet is needed, the volumeand the weight of the transducer are minimized. The transducer can be made of a PCB (Printed Circuit Board) circuit, can be made into a flexible circuit, and is suitable for measuring a tested piecewith an irregular surface and a tubular test piece.

Description

technical field [0001] The invention relates to ultrasonic testing technology in the field of non-destructive testing, in particular to an omnidirectional SH wave electromagnetic ultrasonic transducer without permanent magnets and a design method thereof. Background technique [0002] In the fields of structural health monitoring, guided wave tomography, and ultrasonic phased array inspection, the application of transducer arrays to large-area panel inspection has great prospects. Since the transducer is the basic element in the array system, a lot of research has focused on the development of various guided wave transducers in the field of non-destructive testing and structural health monitoring. [0003] Guided wave, that is, the Lamb wave and SH wave propagating in the plate, compared with the Lamb wave, due to the non-dispersive nature of the low-order SH0 mode, the propagation process is not affected by the fluid load, making the SH wave in the nondestructive testing A...

AI Technical Summary

Problems solved by technology

Ultrasonic imaging has higher requirements for transducers. The traditional unidirectional SH wave transducer can no longer meet the needs of imaging. Therefore, it is urgent to develop a transducer that can excite and receive omnidirectional SH waves. In the research, there are basically no omnidirectional SH wave transducers that can excite and receive omnidirectional SH waves and can be moved for detection.

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