The distortion analysis of magnetic excitation (DAME) method has been recently proposed to facilitate magnetic measurements for non-destructive testing in which pick-up coils are not necessary. This method is based on the distortion effect that the permeability of the sample generates on the voltage across the excitation coil. The aims of the method presented in the present paper are to amplify this distortion effect using a current mode-controlled magnetization and to extract a distortion signal, of high signal-to-noise ratio (SNR), from the voltage measured in the excitation coil by means of a demodulation technique. This methodology is applied to different skin passed steels to characterize the elongation level, which is still a challenge for conventional non-destructive electromagnetic techniques. The relationships between the parameters derived from the distortion and from the hysteresis are studied. Measurements according to the DAME method are performed to verify the improvement in sensitivity for magnetic characterization.

最近已经提出了磁激励的畸变分析（DAME）方法，以促进用于无损检测的磁测量，在无损检测中不需要拾波线圈。该方法基于样品磁导率在励磁线圈两端的电压上产生的畸变效应。本文提出的方法的目的是使用电流模式控制的磁化强度来放大这种失真效应，并从励磁线圈中测得的电压中提取出具有高信噪比（SNR）的失真信号。通过解调技术。该方法学适用于不同的光整钢，以表征伸长率，这对传统的无损电磁技术仍然是一个挑战。研究了从失真得到的参数与从滞后得到的参数之间的关系。进行根据DAME方法的测量，以验证磁性表征灵敏度的提高。