薄膜涂层材料中的广义瑞利波

THE PROPAGATION OF GENERALIZED RAYLEIGH WAVES IN A COATED MATERIAL

基于弹性动力学的线性理论,建立了涂层材料中广义瑞利波传播的理论分析模型,并且由波动方程和边界条件推导了波的频散方程.分析了慢层和快层对相速度频散的影响,给出了不同层厚-波长比和不同涂层-基体密度比情况下广义瑞利波相速度的理论解.算例分析分别比较了慢层和快层结构中波的相速度、群速度,以及随深度衰减的位移与应力振幅.另外,相速度曲线和位移振幅曲线与文献中给出的结果吻合,验证了理论模型和分析过程的正确性.

Based on the linear elastodynamics theory, an analytical model is established for the propagation of generalized Rayleigh waves in a coated structure. Moreover, the dispersion equation is derived from the wave motion equations and the boundary conditions. The theoretical solutions of the phase velocity are obtained for the cases of different ratios of the coating thickness to the wavelength, and different density ratios of the coating to the substrate, by considering respectively the influence of low layers and fast layers on the phase velocity. In the numerical examples, the phase velocities, group velocities and the attenuating amplitudes of displacement and stress component in a slow layer structure are compared with those in a fast layer structure. Besides, the model and the analysis are validated by comparing with those in the references. This paper provides a theoretical basis to determine the material parameters of various coating media by means of surface wave method.