摘要

Nondestructive testing of thick multilayered structures is challenging because of the number of layers and the increased plate thicknesses. In this paper, ultrasonic guided waves are applied to detect and characterize delaminations inside a 23-layer hybrid structural laminate that consists of metallic, glass fiber composite and adhesive materials. A semi-analytical finite element (SAFE) technique is used to generate dispersion curves and wave structures for the purpose of selecting appropriate wave structures and hence test points for discontinuity detection and characterization. One guided wave mode and frequency is chosen as an example to achieve large in-plane particle displacements at regions of interest. The high sensitivity of the selected guided wave mode and frequency is first validated in a finite element model that simulates the interactions of the selected mode with a discontinuity. Theoretically driven experiments are then conducted and compared with bulk wave measurements. It is shown that guided waves can well detect and characterize deeply embedded damages inside thick multilayer fiber-metal laminates with suitable mode and frequency selection.

  • 出版日期2010-2