Lamb waves in cubic crystals: crossing fundamental branches

Abstract

The current research is concerned with the study of Lamb waves propagating in a traction-free plate with cubic anisotropy along the crystallographic axes. Splitting all cubic crystals into two non-intersecting classes revealed either the appearance or disappearance of the crossing points of the fundamental branches. The spectral analysis of the resolvent matrix in the vicinity of the crossing points showed existence of a two-fold degeneracy with two distinct kernel eigenvectors and absence of the non-semisimple degeneracy, meaning stability of the flexural and symmetric fundamental branches passing through the crossing point.

Keywords:

• Lamb wave
• dispersion
• cubic crystal
• classification
• crossing point

Additional information

Funding

The work was supported by the Russian Science Foundation (Grant no. 20-11-20133).