中文摘要：

在粘接界面具有弹簧模型的连接条件下，利用粘接层界面的单次反射和透射推导了反射系数的模与入射角的关系，研究了粘接材料的改变对界面反射特性的影响，以及弱粘接条件下超声波的反射系数的模随着不同刚度比和入射角的变化规律．数值模拟结果表明：横波入射时，存在临界角，反射系数的模在临界角附近变化较大；临界角随上层材料的不同而变化，反射系数的模在临界角处取得极小值；界面脱粘时，随着临界角增大，反射系数模的最小值逐渐减小；在弱粘接条件下，随着界面刚度比减小，当入射角度小于某角度时，反射系数的模整体变大．

英文摘要：

According to the ultrasonic propagation characteristics and spring model condition, the relationship between the reflection coefficient of bonding interface and incidence angle under once reflection echo was derived, the influence on the reflective properties of bonding interface with the change of bonding material were studied, and the reflection coefficients of weak bonding interface with different stiffness ratio and incidence angle were calculated. Numerical simulation results show that when oblique incidence wave is S-wave, there is a critical angle, and the reflection coefficient changes greatly under the critical angle; critical angle varies with the changing of the upper material, and the reflection coefficient reaches the minimum under the critical angle; when debonding, with the increase of the critical angle, the minimum reflection coefficient decreases; for the weak bonding interface , with the stiffness ratio decreases, the reflection coefficient drifts upward when the incidence angle is smaller than a certain angle.