Belloncle Valentina Vlasie, Rousseau Martine
Laboratoire de Modélisation en Mécanique, Université Pierre et Marie Curie, UMR CNRS 7607 Case 162, Paris Cedex 05, France.
Ultrasonics. 2006 Dec;45(1-4):188-95. doi: 10.1016/j.ultras.2006.09.003. Epub 2006 Oct 9.
The aim of this paper is to evaluate the influence of the surface free energy upon the propagation of the eigenmodes of structures, by studying successively (a) the Rayleigh wave for an elastic half-space, (b) the Lamb waves for an elastic layer, and (c) the guided modes for a tri-layer structure (e.g., metal/adhesive/metal). The surface free energy is a parameter which appears in the jump conditions of stresses and displacements at each interface, and which consequently modifies the eigenmodes, solutions of the boundary conditions system. As expected, the Rayleigh wave is dispersive and its velocity increases when the surface free energy increases. In the same way, the velocity of Lamb waves also increases except at normal angle of propagation where the surface free energy does not arise. Moreover, near the Rayleigh angle, the behaviour of the A(0) and S(0) Lamb modes varies strongly according to the surface free energy. Similar results are observed for the tri-layer structure.
本文的目的是通过依次研究（a）弹性半空间中的瑞利波、（b）弹性层中的兰姆波以及（c）三层结构（如金属/粘合剂/金属）中的导模，来评估表面自由能对结构本征模传播的影响。表面自由能是一个出现在每个界面应力和位移跳跃条件中的参数，因此会修改作为边界条件系统解的本征模。正如预期的那样，瑞利波是色散的，并且当表面自由能增加时其速度会增加。同样，兰姆波的速度也会增加，但在表面自由能不起作用的垂直传播角度处除外。此外，在瑞利角附近，A(0)和S(0)兰姆模的行为会根据表面自由能而发生强烈变化。对于三层结构也观察到了类似的结果。
