电磁声发射检测技术的涡流激励方法

摘要

The paper demonstrates the feasibility of acoustic emisslon（AE） reduced 19y eday current through analyzing the change of deformation at the tip of defect with the exciting current through the finite element method （FEM） of electromagnetically induced acoustic emission （EMAE）. In addition, the deformation nature of defect is determined by the fracture mechanics. The experiment of EMAE is carried out. Acoustic emission signals of the defect are received and the crack is located by AE signals. The established feature of AE signals proves that FEM is correct, which provides a firm theoretical and experimental foundation to the direct calculation and analysis of amplitude and frequency feature of EMAE.%本文使用电磁声发射的有限元分析模型,深入分析了缺陷顶点的形变随激励电流的变化规律,论证了涡流激励声发射的可行性,并引入断裂力学对缺陷处形变的性质进行了分析。进行了基于涡流加载的电磁声发射实验,采集到了来自不同激励电流下缺陷的电磁声发射信号,实现了对裂纹的定位,得到了声发射信号的波形特征,验证了有限元分析模型的正确性,这为使用有限元方法直接计算和分析电磁声发射信号的幅频特性提供了坚实的理论和实验基础。