Research On Flexible Planar Array Electromagnetic Sensor Based On Printing Electronic Technology

Electromagnetic array detection technology detect by multiple detection unit,it can achieve a large area detection through just one scan.At the same time,this technology can maintain high resolution,and the results can be imaging display,which is beneficial to improve detection efficiency and detection performance.Therefore,this technique has important application value.The key to electromagnetic array detection technology lies in the design and manufacture of array sensor.To meet the requirements of nondestructive crack detection on components with complicated shapes,miniaturization,high sensitivity,being more flexible and being applied in arrays are the key points of researches on eddy current sensors.However,due to the limits of processing precision of conventional FPC method,it is difficult to simultaneously satisfy the requirements of small size and multi-turn count of the detection unit of the array sensor,since high sensitivity and high spatial resolution of the sensor cannot be achieved simultaneously.In this study,flexible planar eddy current sensor array,which can be applied to detection of micro defects on the surfaces of metal samples with complicated shapes,was fabricated via an emerging nanoimprint lithography technology.The paper first analyzes the detection mechanism of planar array electromagnetic sensors.Next,model of planar eddy current sensor array was established by COMSOL simulating software.Effects of structural parameters like turns of detecting coil,thickness of exciting coil and thickness of insulating layer on the sensor's sensitivity were also investigated.Based on the analysis results,the structural parameters of the sensor are determined.Then,the research on the preparation of flexible planar array electromagnetic sensor by printing electronic technology is carried out and a sensor sample has been produced.Finally,an experimental platform was set up to test the performance of flexible array sensor samples.The results show that the designed array sensor meets the requirements of quantitative detection of micro defects and can be applied to nondestructive testing of equipment.The research results of this paper provide theoretical and device support for the electromagnetic array quantitative detection and evaluation of the micro-defects in the complex surface.