磁场对涡流检测线圈影响实验的研究 - 图文

南昌航空大学2012届学士学位论文

磁场对涡流检测信号影响实验的研究

学生姓名：刘宏村 班级：080812 指导老师：宋凯

摘要：钢管与人类生活、生产活动密不可分，其安全性需要保证。生产中一般

采用磁饱和涡流检测实施检测。但施加磁饱和效应后，涡流检测探头获得的信号会不会有漏磁场的信号呢？因此，研究钢管磁饱和以后涡流检测信号的来源对钢管涡流检测的发展有巨大意义。

本文首先自行研制了涡流探头，进行了对自行研制的检测探头灵敏度进行了测试，选择了达到实验灵敏度要求的探头。

对比了穿过式线圈对不加永磁体的铝管涡流检测信号与加永磁体的铝管涡流检测信号，结果表明不论是否加以永磁体，涡流探伤能够对缺陷进行检测且检测结果基本一致。说明用穿过式线圈涡流检测中，是否加以永磁体，涡流信号都是涡流效应产生的。

最后，在10mm厚铝板下使用永磁体模拟漏磁场源，用放置式探头在铝板上方扫查永磁体对应部位，此时涡流仪上有信号显示。相同的检测条件，在10mm厚铝板下分别放置一小钢块和铝块，用放置式探头依次扫查刚块和铝块对应部位，涡流仪没有信号显示。结果表明涡流仪无法感知10mm厚铝板下磁导率和电导率变化。综合表明漏磁场信号能被涡流仪检测到，强磁场会对涡流检测产生影响。

关键词：磁饱和 漏磁场 涡流检测 钢管

指导老师签名：

南昌航空大学2012届学士学位论文

Magnetic field to affect the experimental study of eddy current testing signals

Student name : liuhongcun Class: 080812 Supervisor:SongKai

Abstract: Stell Pipe and human life and production activities are inseparable,the

need to ensure their safety. Implementation of the detection of magnetic saturation eddy current testing is commonly used in production. Imposed magnetic saturation effect, eddy current testing probe signal will not be tainted signal of the magnetic field it? Therefore, the study of steel magnetic saturation after eddy current testing signal source has a huge significance for the development of the steel pipe eddy current testing.

This article first self-developed eddy current probe, were tested on the detection sensitivity of the probe developed by selecting the probe to reach experimental sensitivity requirements.

Contrast through the coil results show that the aluminum tubes without permanent magnet eddy current detection signal and increase the permanent magnet aluminum tube eddy current detection signal, whether or not to be permanent magnets, eddy current inspection to defect detection and test results are basically the same. Instructions to use through the coil eddy current testing, whether it be a permanent magnet, eddy current signals are generated by eddy current effects.

南昌航空大学2012届学士学位论文

10mm thick aluminum plate using simulation of permanent magnet leakage magnetic field source, the aluminum top of the placed probe to scan the corresponding part of the permanent magnet, eddy current instrument signal. The same testing conditions, the 10mm thick aluminum plate placed on a small steel block and the aluminum block, place the probe followed by scanning just block and aluminum block, the corresponding parts of the eddy current instrument, there is no signal. The results show that the eddy current instrument is unable to perceive the magnetic permeability and electrical conductivity change in the 10mm thick aluminum plate. Integrated to show that the leakage magnetic field signal can be eddy current instrument detected, eddy current testing of a strong magnetic field will have an impact.

Keyword: magnetic saturation leakage magnetic field Eddy current testing steel pipe

Signature of Supervisor:

南昌航空大学2012届学士学位论文

目录

1绪论 .......................................................................................................................... 1

1.1选题背景及研究意义...................................................................................... 1 1.2涡流检测研究概况.......................................................................................... 2 1.3论文主要工作.................................................................................................. 3

2涡流检测的概述 ................................................................................................. 5

2.1涡流检测基本理论.......................................................................................... 5 2.2涡流检测技术的概述...................................................................................... 8

3检测系统设计及涡流信号的研究 ............................................................ 10

3.1试样及实验装置............................................................................................ 10 3.2探头的研制.................................................................................................... 12 3.3磁特性影响的涡流检测试验研究................................................................ 15

4结论与展望 ......................................................................................................... 23

4.1全文主要结论................................................................................................ 23 4.2对下一步工作的建议.................................................................................... 24

参考文献.................................................................................................................. 25 致谢............................................................................................................................ 26