An approach to propagation of Stoneley waves along statistically rough material interfaces

Przedstawiono model propagacji fal typu Stoneleya (SW) wzdłuż statystycznie nierównej płaszczyzny łączącej dwa izotropowe ośrodki sprężyste. Skorzystano z metody funkcji Greena. Powierzchnię zamodelowano normalnym, izotropowym w szerszym sensie polem losowym. Uzyskano charakterystyki statystyczne zaburzonego pola dynamicznego. Praca stanowi fragment szerszej teorii badań nieniszczących międzypowierzchni materialnych.The continuing development of surface acoustic wave technology, with growing role of the high frequency region, stimulates the need for a more comprehensive study of the effect of various surface and interface inhomogeneities on the propagation characteristics of such waves. Although this topic has been treated for a long time (references, see e.g. [3]), the existing solutions essentially concern very simplified model schemes, basing predominantly on perturbation techniques. The paper deals with propagation of Stoneley waves on rough interfaces between two different materials. The surface profile is modelled by the random field with the known mean value and the correlation function. We use a method based on the Green function technique combined with a well known approach [4] which resides in replacing a rough interface between two different materials by an ideal one with a randomly distributed stress tensor. This enables us to find consistent closed form expressions describing the frequency power spectrum of the random field of displacements