Features of Excitation of an Electromagnetic Acoustic Transducer under a Waveguide Method of Testing

Abstract

Widely spreading waveguide techniques for non-destructive testing of extensional objects, including the application of electromagnetic-acoustic technologies in the changing market of electronic components require the search for new approaches to the design of electronic equipment. Circuitry solutions that are necessary for constructing a probe pulse generator in the measuring and information system that implements the waveguide technique for non-destructive testing of extensional objects were considered. The operational requirements for the device are determined and the necessary characteristics of the components of the pulse generator that affect its behavior in the formation of a shock pulse for the EMA transducer are estimated. The criterion for estimating the work of the shock pulse generator in the form of the reverberation-noise characteristic duration is obtained. Frequency analysis of the excitation system of the emitter of the radiator is carried out depending on the number of turns of the radiator and the magnitude of the active resistance in the system. Frequency analysis of the excitation system of the emitter of the EMA transducer depending on the number of turns in the transducer and the magnitude of the active resistance in the system was done. The maximum pulse field in the EMA emitter is estimated and the optimum number of turns is determined for it. The maximum pulse field in the EMA emitter was estimated and the optimum number of turns was determined. Based on the evaluation of the EMA emitter and generator characteristics an electric adapter for the ADNH flaw detector, connected to the generator output and to the receiver input, which allows using a piezo transducer in a combined mode was developed. The device was tested on the rods of composite reinforcement. The obtained value of the RNC was about 500 μs (corresponding to 1.2 m).