Eddy Current Testing method is the process of inducing small electrical currents into a conductive article and observing the interaction between the article and the currents. A number of factors within the article will affect the flow of these eddy currents and means exits for relating test indications to these factors.

Eddy Current testing can be applied to cylinders, tubing, sheets and coatings, and provides a means for measuring conductivity, detecting discontinuities, and determining the thickness of coatings or palting on articles.

Advantages of Eddy Current Testing:

¨    Accurate measurement of conductivity

¨    Immediate Indication

¨    High Speed Testing

¨    Detection of small discontinuities areas

¨    Non contacting

Limitations of Eddy Current Testing:

¨    Specific nature of discontinuities are not clearly identified

¨    Low penetration

¨    Testing of ferro-magnetic metals is something difficult (see Remote Field Technique)

¨    A permanent record of discontinuity is often not available