Delamination monitoring of CFRP laminate using the two-stage electric potential change method with equivalent electric conductivity

Carbon fiber reinforced plastics laminate (CFRP) has a high specific strength and stiffness compared to conventional metals, although it is very sensitive to impact. A low impact leads to a delamination and results in the deterioration of the structural reliability. The present study employs a two-stage electric potential change method (EPCM) to identify delamination. In the methods, delamination is estimated using response surfaces, which require numerous experiments. An equivalent electric conductivity method is introduced to reduce this number. Delaminations are successfully estimated using response surfaces based on the results of the finite element method with equivalent electric conductivity.

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