Application of eddy current techniques to inspect friction spot welds in aluminium alloy AA2024 and a composite material
AbstractNew materials and production technologies demand improved non-destructive techniques for inspection and defect evaluation, especially when critical safety applications are involved. In this paper two Non-destructive Testing (NDT) applications are presented: the inspection of Friction Spot Welding (FSpW) of AA2024-T351 with and without AlcladTM and a composite material GLAss-REinforced Fibre Metal Laminate (GLARE®) with artificial defects. The two applications were tested by Eddy Currents (EC), using both conventional planar spiral probes and a new EC probe developed by some of the authors, called IOnic probe. Four different FSpW conditions were produced and tested in 2 mm-thick plates of duraluminium with and without AlcladTM. Three defects were introduced in GLARE® aiming to compare the reliability of the different NDT approaches. The experimental results show that the IOnic probe is able to identify different levels of FSpW quality regions by a distinctive perturbation on the output signal, whereas conventional probe cannot distinguish the different FSpW conditions. Regarding the GLARE® application, it was found that IOnic probe can detect the deeper defect easier than the conventional EC probe.