中文摘要：

水平剪切（Shear Horizontal,SH）导波在传播的过程中有对称模式和反对称模式,其相速度和群速度主要取决于试件的厚度和频率之积（频厚积）。利用COMSOL有限元分析软件,建立了钢板缺陷的3-D模型,仿真分析了SH0导波在钢板中的传播特性。仿真结果表明SH波在传播过程中很少发生波束方向的改变,无频散和模式转换,信噪比高。利用电磁超声方法激励SH波,对钢板中的裂纹和焊缝缺陷进行了实验,验证了仿真结果的正确性及可行性,为超声导波在板材缺陷检测中的应用提供基础。

英文摘要：

Shear Horizontal （SH） wave has two modes in the process of transmission： symmetrical mode and anti- symmetric mode, and its phase velocity and group velocity mainly depend on the product of thickness and frequency of specimen. The paper sets up a three-dimensional model for steel plate defects by using COMSOL finite element analysis software, simulates and analyzes the SH0 guided wave propagation characteristics in the steel plate, and concludes that shear horizontal wave has little change in the direction of beam, no dispersion and mode conversion, and high signal to noise ratio in the process of transmission. Meanwhile, we utilize the electromagnetic ultrasonic transducer to generate shear horizontal wave and make an experiment of the crack and weld defect in the steel to test the validity and feasibility of stimulation result, which will provide the basis for the application of ultrasonic guided waves in the plate defect de- tection.