Application Of Electromagnetic Eddy Current Technology In Detecting Internal Defects Of CFRP

Carbon Fiber Reinforced Polymer (CFRP) are widely used in industrial production, public infrastructure construction, aerospace and sports equipment due to its superior performance. However, due to the complexity of the process of production, the process of weaving is easy to produce defects, resulting in high cost of carbon fiber composite materials, it is difficult to be widely used. So it is very important to detect the defects of carbon fiber composite material.There are a lot of defects detection methods for CFRP, such as infrared detection, X-ray detection, ultrasonic detection, etc. these technologies have achieved a certain effect. The use of eddy current nondestructive detection method of CFRP are relatively few. In this paper, based on electromagnetic field theory and finite element analysis, the electromagnetic eddy current testing of carbon fiber composites is studied. The three-dimensional model of the CFRP with the excitation coil is built by Multiphysics COMSOL, and the parameters of the CFRP are analyzed. According to the law of parameter variation, the simulation of defect detection is carried out, and the surface defects and internal defects of CFRPP is extracted by the method of Z axis flux density extremum.Finite element analysis of the electromagnetic eddy current testing of carbon fiber composite materials can guide the research on electromagnetic eddy current testing of carbon fiber composite materials. On this basis, the results of the simulation experiment are analyzed by the method of the Z axis magnetic flux density extremum. The characterization information of three kinds of defects of carbon fiber composite material is obtained. The experimental results show that the excitation coil has higher sensitivity, and can provide more information for detection. After a lot of experiments, the experimental results are in good agreement with the results obtained by the Z axis magnetic flux density extremum. The electromagnetic eddy current testing technique can be used to detect the surface defects and internal defects in the structure of carbon fiber composites.