Film thickness arbitration method - metallographic method

When there is a dispute over the thickness of the coating, there needs to be a unified standard recognized by everyone to detect the locking layer. The results obtained by this recognized method can be used to resolve the dispute, so this method is called the arbitration method. .

At present, the arbitration method for coating thickness testing recognized by various standards is the metallographic thickness measurement method, because this method can directly measure the thickness of the locking layer with a ruler under a microscope, and the error is within 5%, so it is designated as method of arbitration.

For the metallographic test of the coating thickness, it is first necessary to correctly sample and make the inlaid metallographic test piece, which has been introduced in detail in this chapter. It should be noted that in the process of making the test piece, the representativeness of the sampling and the reliability of the test must be ensured. Since the microscope observes the cross-section of the locked layer, the perpendicularity of the section of the coating to the lens and the accuracy of the test results must be ensured . It has a lot to do with it. At the same time, in order to reduce the measurement error, a layer of coating with a different color from the tested coating can be locked on the surface of the coating to be tested, so that it is easy to find the target coating during observation , thereby preventing misreading.