What are the requirements for the coating thickness gauge during use
1. For the metal properties of the magnetic substrate, the magnetism of the base metal of the standard sheet is the same as that of the test piece base metal, and the surface roughness is also similar. For the eddy current method, the electrical properties of the gauge sheet base metal are also similar to those of the test piece base metal.
2. To ensure the thickness of the base metal, check whether the thickness of the base metal exceeds the critical thickness. If not, you can use the 1-point or 2-point method for calibration.
3. The edge effect cannot be measured at the sudden change of the test piece, such as edges, holes and inner corners.
4. The curvature cannot be measured on the curved surface of the workpiece.
5. The readings of each measurement may not be exactly the same, generally due to the operation method and the uniformity of the substrate, so it is necessary to take several readings in each measurement area when using a coating thickness gauge. In addition, the uneven thickness of the covering layer also requires us to perform multiple measurements in any given area. In addition, the roughness of the surface will also affect the measurement results.
6. Before using the coating thickness gauge to measure the coating, first remove any attached substances on the surface, such as dust, grease and corrosion products, etc. When cleaning, be careful not to damage the coating to be measured.
