Measurement of Nonlinear Guided Waves

Characteristics of nonlinear guided waves provide information about the current state of the material that comprises the waveguide. Notably, the information is related to the material's microstructure, which in turn influences the strength properties. However, the dispersive nature of guided waves makes their nonlinear characteristics more complicated than those of bulk waves. This chapter strives to describe nonlinear features of guided wave propagation including higher harmonic generation and wave mixing. It provides a methodology for selecting wave modes and frequencies that provide the best opportunities for measurements as well as measurement techniques and a glimpse of some recent results.