Damage Imaging in Composite Laminates Using Phase Reversal Method.

A novel Lamb wave-based Phase Reversal Method (PRM) for damage imaging in composite laminates is proposed. The phase spectrum information of the scattering waves reflected from the defect was analyzed. The reflected waves were reconstructed by reversing the phase angle along the propagation path using Inverse Fourier Transform. Then the damage index was defined by the properties of the reconstructed waves. The anisotropic characters of the composite laminates will not affect the reconstruction of the wave form, because of the phase reversal process is applied along each propagation path, which makes the PRM is a proper and effective method for damage imaging for composite laminates. A finite element composite model with damage was simulated in numerical analysis, and the Lamb wave was generated and reflected by the defect. The phase spectrums of the reflected signals received by a pair of neighbor sensors were compared and reversed to detect the damage. In the absence of the baseline data and the parameters of the composite laminates, including dispersion characteristics and anisotropy, we successfully imaged the damage area using PRM algorithm. This result indicated a great potential of the novel proposed method in damage imaging and structural health monitoring for composite laminates. [ABSTRACT FROM AUTHOR]