高速漏磁检测的磁后效及其作用机理研究

项目名称： 高速漏磁检测的磁后效及其作用机理研究

项目编号： No.51275193

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 机械、仪表工业

项目作者： 康宜华

作者单位： 华中科技大学

项目金额： 70万元

中文摘要： 漏磁无损检测技术因穿透能力强且不受非磁性介质影响而被广泛应用于铁磁性材料的安全质量检测。针对目前漏磁检测速度受限而难以胜任高速铁轨、煤矿钢丝绳及石油管具等高速（3 m/s以上）检测问题，提出高速漏磁检测中存在着磁后效（磁化滞后的简称）副作用影响而制约着检测速度提高的假说，采用回转替代纯直线运动的高速磁化检测方法，结合磁感应强度逐渐达到稳定状态的弛豫时间以及过程理论，探索证明高速运动下磁后效影响作用，获得高速状态下铁磁性材料的动态磁化特性（磁后效影响）及漏磁检测机制，进而建立一种在时间和空间上超调饱和磁化的高速漏磁检测方法，以突破漏磁检测低速瓶颈，实现高速高精漏磁检测技术，完成上述如高速铁轨等铁磁性材料的高效安全质量检测；最后在铁磁性材料的高速动态磁化规律（磁后效影响）基础上形成一套高速漏磁检测理论，以丰富漏磁无损检测学科内容。

中文关键词： 钢管；高速；漏磁检测；动生涡流；磁化滞后

英文摘要： MFL (Magnetic flux leakage) nondestructive testing is widely used in the safety and quality inspection of ferromagnetic materials due to its testing feature of strong penetrability and its freedom from the effect of the non-ferromagnetic medium. For the failure of MFL to detect the high-speed railway, wire rope for coal mine and oil pipe tool in high speed (over 3 m/s) owning to its current testing speed limit, the assumption that the magnetic aftereffect influence exists in the high-speed MFL testing and restricts the increase of testing speed is proposed. Then, the verification of magnetic aftereffect influence appearing in the high-speed is conducted by using the high-speed MFL approach of rotary motion instead of linear one, combined with the relaxation time and process theory that the magnetic induction gradually achieves the stable state. Meanwhile, the feature of dynamic magnetization (magnetic aftereffect influence) and MFL mechanism are obtained in the high-speed testing state. Further, a high-speed MFL method based on the saturated magnetization advanced in time and space is provided. The new method could break through the bottleneck of low-speed detection, could realize the high-speed and high-precision MFL testing technology and finally could accomplish efficiently the safety and quality inspection o

英文关键词： steel pipe；high speed；MFL(magnetic flux leakage)；motional eddy current；magnetization time lag