EDDY CURRENT TESTING OF METALS.

Eddy currents can be used for testing metals for changes in composition, structure and hardness, and for detecting and measuring surface and sub-surface defects. They can also be applied to measuring changes in dimensions of rods and tubes and of thicknesses of metal plates and of non-metallic coatings on metal substrates and of metal coatings on non-metallic substrates. Applications include the examination of metal structures and components of all sizes, tubes and pipes, weldments and bolt-holes, in areas such as the manufacture and operation of aircraft, and nuclear energy installations.