Eddy current testing utilises the principles of electromagnetic induction to detect flaws in conductive materials. Eddy current testing can detect very small cracks in or near the surface of the material, the surfaces need minimal preparation, and physically complex geometries can be investigated. It is also useful for making electrical conductivity and coating thickness measurements.

This form of testing relies on the attraction of magnetic particles to the flux leakage when an eddy current is passed through the material. This is an indication of the flaws existence, this flux leakage is caused by the flaw in the ferromagnetic material for which is being tested. A sample eddy current trace is shown below:

The testing devices are portable, provide immediate feedback, and do not need to contact the item in question.

Eddy current inspection has recently been employed to inspect for cracking on welded items without the need to remove paint. The instrument we use is able to store defect details and upload them to computer.

LTC intend to develop further into this field, employing this technology on forged components, for example.

All our digital NDE equipment is from the same “family”, thus enabling common software to combine results from differing methods in reports.