提出一种基于电场测量的无损检测方法,该方法通过检测通电试件外电场的变化来实现内外缺陷的非接触检测。对通电试件的电场进行仿真计算,模拟出电场的分布并分析了缺陷电场的信号特征。以半导体材料为被测试件,在高电压激励下采用被动式的共面电容探头探测到了内外缺陷的电场信号。实验与仿真结果的一致性表明,采用该方法对金属和非金属材料进行内外伤的检测具有一定的可行性。
An EFM nondestructive testing method was presented herein.This method offered a possible route to perform the no-contacting inspection for internal and external defects by detecting the electric field variations outside the current-carrying specimen.The electric field of a current-carrying specimen was simulated,and the signal characteristics of defects were discussed.In the preliminary experiments,a semiconductor material was used as the tested specimen,and a passive coplanar capacitor probe was employed to induce the electric field variations.In the case of high voltage exciting,the probe detected the electric field signals of internal and external defects.The consistency of the simulation and experimental results imply that the EFM method has the potential of inspecting internal and external defects in the metal and nonmetal materials.