多频涡流检测系统的设计

发布时间：2018-01-07 09:10

本文关键词：多频涡流检测系统的设计　出处：《天津工业大学》2017年硕士论文　论文类型：学位论文

【摘要】：在当今工业安全生产中,人们发现轴类、压力容器、核运行设备以及飞行器等容易出现断裂、裂纹、气泡等问题,这些微小的缺陷不仅造成了巨大的经济损失,甚至导致灾难性的事故。对缺陷的检测有很多种方法,例如红外检测、X射线检测、超声检测等,其中超声波检测是一种比较认可的检测方法,但是因其不适合持续观测缺陷的变化而发展受阻。因此,本课题提出了一种多频涡流无损检测的方法,不仅能够对样板缺陷进行持续观测,而且具有灵敏度高、速度快、适用场合广等优点。该系统使用多频涡流技术,利用空间磁场传感器HMC1043对铝板的表面及其近表面微小缺陷进行检测,且能够对缺陷的特征(长度、宽度、深度)进行表征。采集数据使用的芯片是STM32F103ZET6,将采集的数据使用串口上传到上位机,同时在TFTLCD液晶显示屏上对采集的数据进行实时显示。本文首先介绍了电磁涡流的技术特点以及发展状况,并对特殊探针的发展进程进行了详细的介绍,结合实际的工程项目对电磁涡流检测方法进行分析,确定实验中无损检测的方法。接着介绍系统的硬件、软件的设计以及相关调试等。其中在硬件方面,设计了一种稳定性与灵敏度较高的矩形线圈,可以在很大程度上提高检测的灵敏度。最后使用该检测系统对铝板缺陷进行了扫描实验,并对采集的结果进行分析。文中使用控制变量法分别讨论了励磁频率以及缺陷几何尺寸对扫描图像的影响,同时也验证了该系统能够很好的检测铝板等材料的表面以及近表面的微小缺陷,对实际涡流无损检测具有较高的参考价值。
[Abstract]:In today's industrial safety production, it is found that shafts, pressure vessels, nuclear equipment and aircraft are prone to fracture, cracks, bubbles and other problems, these tiny defects not only caused huge economic losses. There are many methods to detect defects, such as infrared X-ray detection, ultrasonic detection and so on, among which ultrasonic detection is a relatively recognized detection method. However, it is not suitable for continuous observation of defects and development is hindered. Therefore, a multi-frequency eddy current nondestructive testing method is proposed, which not only can be used for continuous observation of template defects, but also has high sensitivity. The system uses multi-frequency eddy current technology and the space magnetic field sensor HMC1043 to detect the small defects on the surface and near surface of aluminum plate. The chip used to collect data is STM32F103ZET6, which can upload the collected data to the host computer using serial port. At the same time, the data collected on TFTLCD LCD is displayed in real time. Firstly, the technical characteristics and development of electromagnetic eddy current are introduced in this paper. The development process of the special probe is introduced in detail, the electromagnetic eddy current testing method is analyzed in combination with the actual project, and the non-destructive testing method in the experiment is determined. Then, the hardware of the system is introduced. Software design and related debugging. In hardware, a kind of rectangular coil with high stability and sensitivity is designed. The sensitivity of the detection can be improved to a great extent. Finally, the scanning experiment of aluminum plate defects is carried out by using the detection system. The control variable method is used to discuss the effect of excitation frequency and defect geometry on the scanning image. At the same time, it is also proved that the system can detect the small defects on the surface and near surface of the aluminum plate and other materials, which has a high reference value for the practical eddy current nondestructive testing.
【学位授予单位】：天津工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP274

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