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表面波作为超声波的一种特殊形式，由于其传播特性，使得通过改变频率检测距物体表面不同深度处的初始应力成为可能，因此，各种材料的表面波声弹理论与实验技术的研究不断受到重视。本文从弹性波和有限变形理论出发，推导了表面波在有初始应力的各向同性弹性体中传播时，物体表面应力与超声波传播速度之间的一般关系。对作为飞机坐舱的航空透明件YB－3有机玻璃试件进行了声弹性实验，同时还给出了由实验数据回归的三次多项式声弹公式。实验结果表明，此类材料中声表面波的传播速度对其中的应力的依赖关系只在很小的范围内是近似线性的，而在其强度极限内总体上为非线性关系。
As a special form of ultrasonic wave, surface wave has made it possible to detect the initial stress at different depths on the surface of the object by changing the frequency due to its propagation characteristics. Therefore, the research on surface acoustic wave theory and experimental techniques of various materials has been continuously Pay attention. Based on the theories of elastic wave and finite deformation, this paper deduces the general relationship between the surface stress and the propagation velocity of ultrasonic wave when the surface wave propagates in the isotropic elastic body with initial stress. The acoustic elasticity experiment was carried out on YB-3 Plexiglas specimen, which is an aircraft transparent cabin. At the same time, the cubic polynomial acoustic bounce formula, which is regressed by the experimental data, is given. The experimental results show that the dependence of SAW propagation velocity on the stress in these materials is approximately linear over a small range and generally non-linear within the strength limit.