Study On Detection Method Of The Internal Defects In Carbon Fiber Reinforced Plastic

As a construction engineering material,carbon fiber composite material has the advantages of high strength,low density and high corrosion resistance.The comprehensive properties are more advantageous than single materials and can meet the needs of various occasions and environments.It is widely used in the field of modern civil engineering.However,various defects may occur during the processing and long-term use of carbon fiber composites.The existence of these defects will seriously affect the performance of materials,and even there are safety risks.Therefore,it is particularly important to select appropriate methods for the detection of internal defects and the identification of defect types.Ultrasonic phased array technology is a new technology of multi-beam scanning imaging in industrial nondestructive testing.It has the advantages of high efficiency,controllable sound beam and fast imaging performance.The research of ultrasonic phased array technology in the field of defect detection of carbon fiber composites has been carried out in the world,and has become a research hotspot for scholars.In this paper,the defect detection method of carbon fiber composites is studied.The finite element analysis software is used COMSOL Multiphysics simulate the sound field of carbon fiber composites.In the simulation,the defect model and the test specimen model are established;the material parameters are set according to the properties of the actual material,including the properties and dimensions of the material;the parameters of determining the one-dimensional linear array include the center frequency,the number of elements and the center spacing of the elements;and the appropriate longitudinal wave sound velocity of the ultrasonic wave is determined.After setting the sound field parameters,the sound field simulation is carried out.The ultrasonic propagation imaging effect diagram of different array elements at the same time can be obtained.The appropriate experimental parameters in the experimental scheme are further determined.On the basis of sound field simulation,the experimental scheme is determined.The defects of carbon fiber composites can be detected by ultrasonic phased array detection system,and the original data of phased array flaw detector can be extracted and processed.A scanning images and C scanning images are obtained.The A scanning image and the C scanning image can be analyzed to know that there are defects in the material and the type,contour and position characteristics of the defects can be preliminarily judged.In order to accurately analyze the types of defects detected in carbon fiber composites on the basis of unknown defect types.In order to deal with the ambiguity of internal defect diagnosis of carbon fiber composites,the correlation coefficient method of simple neutrosophic sets is adopted,and the characteristics of internal defects are extracted by ultrasonic phased array detection technology.The SNSs of each defect types are established according to defective feature vector.In this paper,the correlation coefficient method of simple neutrosophic sets is used to diagnose the internal defect types of materials.The experimental results show that this method can effectively diagnose the internal defect types of carbon fiber composites.