Thickness and Coating Measurement Echo to Echo Technique on the Alphagage+

This application note is about whether Echo-To-Echo has the ability to either ignore the paint/coating and measure just the substrate or measure both coating and substrate at their independent velocities.

In the past, the customer would spend the time and money to remove the coating knowing the thickness of the coating has nothing to do with the integrity of the substrate but ever more, the coating thickness introduces an error. In addition, the part then needs to be re-painted. When using a conventional gage without echo to echo (ignoring the coating), the error is simple to calculate. The thickness on conventional gages is based on one sound velocity, that typically of steel.