Can Eddy Current NDT work for Inspecting Coating Thickness?Coating Thickness Assessment
To obtain quantitative readings, a calibration piece with several different thickness of coating in the range of interest is essential, and a calibration curve created. Some instruments have an intrinsic function as part of conductivity measurement for obtaining direct readings. For the more complex case where the coating is conductive, then the following needs to be taken into account. The two materials must have different conductivities and/or relative permeabilities and the top coating must be non-magnetic. Choose a frequency that will make the effective depth of penetration equal the nominal wall thickness. If the surface coating has higher resistivity than the lower coating, then by using a frequency that is sufficiently low to penetrate the surface coating, results will be similar to that for non- conductive coatings. Wall Thickness AssessmentThis is possible in the same way as it is possible to determine non-ferrous conductive coating thickness and the same rules apply about choice of frequency.
If you have a coating thickness application that you think you maybe able to solve through using Eddy Current NDT, please email us at "> You can find out which ETher NDE equipment is best for your application needs by taking a look at our Applications Equipment and Probes Table. |