Non-destructive testing of low-energy impact in CFRP laminates and interior defects in honeycomb sandwich using scanning pulsed eddy current

Abstract

a b s t r a c tWith the growing interest to use composite materials and honeycomb sandwich panels in industrial fields, much attention is devoted to the development of non-destructive testing (NDT) techniques for the detection and evaluation of defects. In this work, scanning pulsed eddy current (PEC) was investigated and two features, representing the magnetic field intensity and conductivity, were used to characterise the different types of defects in carbon fibre reinforced plastics (CFRP) laminates and honeycomb sandwich panels. The experimental results show that the low energy impact from 4 J to 12 J, conductive and non-conductive insert defects can be effectively detected and evaluated using the proposed methods. The effectiveness was verified and the advantages of scanning PEC were addressed through comparative studies with flash thermography and shearography.

Defect characterisation using pulsed eddy current thermography under transmission mode and NDT applications

“…However, there are no abnormal hot spots on the reconstructed image for 4 J impact. Although, we observed the slight thickness change on the 4 J impact area using scanning pulsed eddy current [38]. …”

Pulsed Eddy Current Non-destructive Testing and Evaluation: A Review

“…However, its relative proneness to impact damage immediately leads to the industrial requirement of effective NDT techniques for ensuring its integrity. On the light of this, researchers have investigated the application of eddy current NDT, including PEC, to detect and characterize defects and damage in CFRP [90], [91]. The CFRP problem is particularly challenging due to its anisotropic characteristic.…”

Structural health management utilization for lifetime prognosis and advanced control strategy deployment of wind turbines: An overview and outlook concerning actual methods, tools, and obtained results

“…Although in the cases of relatively low conductivity of composites [57], it is still sufficient to apply Eddy current testing targeting to detect different changes such as delamination, fiber break, matrix cracking, layer misalignments, and similar. For instance, Heuer et al [58] applied eddy current testing to the detection of changes in Raw Carbon Fiber (RCF) and CFRP materials.…”