飞机复合材料构件的超声检测方法研究

发布时间：2018-07-12 09:07

本文选题：复合材料 + 超声检测　；参考：《中国民航大学》2017年硕士论文

【摘要】：由于复合材料的物理特性,其组成的结构件在长期使用中容易产生分层缺陷,成为飞机飞行过程中的不安全因素。最受欢迎的检测方法是超声无损检测。对超声无损检测技术进行深入研究来确保民航飞机各种结构件的安全是一项具有现实意义的课题。论文首先对超声波的传播特性进行了分析,研究超声波在各向异性介质中的传播,使用PZFlex建立探头声场的有限元模型。其次,根据复合材料本构模型和超声传播特性在PZFlex中实现了超声检测过程的数值模拟,能够得到两类仿真图形,即没有缺陷的回波图形和具有一定缺陷类型的回波图形。然后,在对复合材料检测仿真的基础上,选择A型脉冲反射检测方法,搭建一个数字式超声检测系统,能够完成采集缺陷回波信号、存储在系统中以及对其进行传输等多项工作。最后,采用上述介绍的检测系统和方法对具有缺陷以及没有缺陷的碳纤维复合材料试块进行检测实验,此外,还对采集到的缺陷回波信号进行了研究分析工作。本课题选择超声检测技术对碳纤维复合材料层板在民航飞机上的应用进行深入的研究和分析,并以多层板中常出现的分层缺陷为研究对象,利用有限元法对检测的过程进行数值模拟,从而得到缺陷的回波仿真图,通过实验得到的缺陷回波验证了仿真模型的合理可行。
[Abstract]:Because of the physical properties of the composite materials, the structural components of the composites are prone to delamination defects in long-term use, which becomes an unsafe factor in the flight process of aircraft. The most popular method of testing is ultrasonic nondestructive testing. It is of practical significance to study the ultrasonic nondestructive testing technology to ensure the safety of all kinds of civil aviation aircraft structures. Firstly, the propagation characteristics of ultrasonic wave are analyzed, the propagation of ultrasonic wave in anisotropic medium is studied, and the finite element model of acoustic field of probe is established by using PZ Flex. Secondly, according to the constitutive model of composite material and ultrasonic propagation characteristics, the numerical simulation of ultrasonic testing process is realized in PZ Flex, and two kinds of simulation graphics are obtained, that is, the echo pattern without defect and the echo pattern with certain defect type. Then, on the basis of testing simulation of composite materials, a digital ultrasonic detection system is built by selecting A-type pulse reflection detection method, which can complete the acquisition of defect echo signal. It is stored in the system and transmitted to the system. Finally, the testing system and method described above are used to detect the carbon fiber composite samples with and without defects. In addition, the collected defect echo signals are studied and analyzed. In this paper, ultrasonic testing technology is selected to study and analyze the application of carbon fiber composite laminates in civil aviation aircraft, and the delamination defects that often appear in multilayer plates are taken as the research object. The finite element method is used to simulate the detection process, and the simulation diagram of the defect echo is obtained. The simulation model is proved to be reasonable and feasible by the experiment.
【学位授予单位】：中国民航大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：V267;TB559

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