Aerospace
Eddy current inspection is often used to find surface fatigue cracks in aircraft structures during aircraft maintenance in-service. For aluminum alloys, high frequencies from approx. 50 kHz to 1 MHz are used for inspection.
Cracks occurring in the skin initiated from rivets or other joints can create during loading of the airframe.
By surface probes, not only cracks from joints and cracks in the skin sheet can be detected, but also other damage such as corrosion or the presence of inclusions in the aluminum alloy, which have a significant effect on the mechanical and fatigue properties of the aluminum alloy.
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Other industry
Detection of surface defects in weld joints, rails and heat-exchanger tubes. These are defects such as crack, presence of corrosion, loss of wall, deformation, dents etc.
