Material parameter determination from time-domain signals transmitted and reflected by a layered structure

摘要

The modeling of the time-domain signals transmitted and/or reflected by a layered structure is very useful for the simulation of wave propagation in the structure containing deteriorated layers, defects and delaminations and for the characterization of material properties in those layers. In this paper, we first present the relations between the signals transmitted and reflected by a layered plate in terms of transmission and reflection coefficients in the frequency domain. The time domain singals transmitted and reflected by the plate are then expressed by use of the inverse Fourier transform. The simulated signals transmitted and reflected by an Aluminum plate and a Titanium plate and a diffusion bonded Titanium plate are compared with measured signals. The inverse problem for the determination of the unknown parameters of the layered plates in the time-domain is also discussed.