Internal Antisymmetric Lamb Waves

A class of antisymmetric solutions of Lamb wave equations with zero strains and stresses on the surface, so-called internal Lamb waves, is studied. Two types of such solutions are found: the first corresponds to the Lamé phase velocity; the second, to phase velocities exceeding the velocity of the expansion wave in an unbounded medium. It is proved that internal waves with the same phase velocity form series, while the frequencies of members of one series are multiples of the frequency of the first member of the series. The same is true for wavenumbers. The profiles of deformed plates and distributions of the maximum stress and shear values are presented.