基于脉冲漏磁检测原理的缺陷分类识别技术

Classification recognition technique of defects based on pulse magnetic flux leakage testing

脉冲漏磁检测是一种快速发展的无损检测方法,而相应的缺陷分类识别是缺陷检测与评估中的关键步骤之一.在介绍脉冲漏磁检测原理的基础上,设计了新型传感器,对不同类型缺陷的标准试件进行了测试;通过对缺陷瞬态差分信号的时、频域特性进行分析,提取了峰值、过零时间以及频谱中一特定频率点的幅值作为特征量对缺陷进行分类识别.实验结果表明该方法可对10 mm钢板表面以及下表面缺陷进行有效的分类识别.

Pulsed magnetic flux leakage(PMFL) testing is an emerging and effective electromagnetic non-destructive testing technique,and the defect classification is a key step to defect detection and evaluation.A new PMFL sensor was designed based on the principle of pulsed magnetic flux leakage testing,and the different types of the defects of standard samples were detected.The peak values,zero-crossing time and the amplitude at some frequency in frequency spectrum were selected as characteristic parameters for the classification recognition of defects through the characteristic analysis of the transient differential signals in time domain and frequency domain.Experiment results show that the proposed defect classification recognition method based on pulsed magnetic flux leakage testing is effective to different types of the surface defects in steel plate specimen of 10 mm thickness.