Research On Non-destructive Testing Technology Of Honeycomb Composite Materials

With the vigorous development of aerospace industry,the importance of composite materials in aerospace field is increasing with their superior properties.In order to ensure the safety and reliability of spacecraft in use,there are very high requirements for product quality,performance and life in the field of aerospace.The research of nondestructive testing methods for honeycomb composites is of great significance because of their structure and properties.Non-destructive testing technology means on the basis of guaranteeing the original shape and properties of materials,it uses optical,acoustic,electrical,magnetic,thermal and radiographic techniques to detect whether there is damage or not.Non-destructive testing technology can be used to detect the surface and interior of the material and make accurate j udgments on defects.In this paper,the honeycomb composites are mainly used as research objects.The simulation of non-destructive testing of typical defects of honeycomb composites is carried out.Different methods are used to detect defects to optimize the detection method,and performed simulation studies using finite element multiphysics simulation software.The finite element method is to divide the large area which needs to be solved into a finite number of small elements which are convenient to solve.The small elements that are decomposed are called finite elements.Each finite element is solved by reasonable assumptions,and then the approximate solutions of each finite element are integrated to obtain the approximate solutions of the whole region.According to the different dimensions of the composite members,the different properties of the materials and the different detection environments,different non-destructive testing methods and the combination of these methods are used to perform non-destructive testing on the composite materials.The infrared thermal wave method is suitable for large-area detection,and the electromagnetic ultrasonic method can also accurately detect under high temperature environment.The tap detection method can detect defects in real time and realize rapid detection,and the optimal detection scheme can be designed according to the characteristics of the tested parts.In this paper,the simulation of infrared thermal wave method for debonding detection of honeycomb composites is studied.The debonding defect of honeycomb composites was judged by surface temperature distribution of honeycomb composites after thermal excitation loading.The size of defect and the difference of skin material were simulated and analyzed.The scratch defect on skin surface was simulated by electromagnetic ultrasonic nondestructive testing method.The principle of electromagnetic ultrasound is analyzed to create a matching electromagnetic ultrasonic transducer.Finally,according to the Lorentz force distribution diagram,the defect situation is analyzed and j udged.To improve the existing knock nondestructive testing system,mainly to optimize its sensors,a multi-layer integrated piezoelectric chip is designed,which has higher sensitivity than the ordinary piezoelectric chip,thereby improving the detection accuracy of knock nondestructive testing.