principle of coating thickness gauge measurement

A protective layer that protects the surface of the material, such as coatings, coatings, overlays, chemically formed films, etc., which is referred to as coating in some national and international standards.

Coating thickness measurement gauge has become an important part of the processing industry and surface engineering quality testing, and it is a necessary means for products to achieve superior quality standards. In order to internationalize the products, China's export commodities and foreign-related projects have clear requirements for the thickness of the coating.

The ultrasonic coating thickness measurementmethods are wedge cutting method, light intercept method, electrolysis method, thickness difference measurement method, which is weighing method, X-ray fluorescence method, β-ray backscattering method, capacitance method, magnetic measurement method and eddy current measurement. Law and so on. The first five of these methods are lossy detection, and the measurement methods are cumbersome and slow, and they are more suitable for sampling inspection.

The X-ray and beta-ray methods are non-contact Non destructive coating thickness gauge, but the device is complicated and expensive, and the measurement range is small. Users must comply with radiation protection regulations due to radioactive sources. The X-ray method can measure extremely thin plating, double plating, and alloy plating. The beta ray method is suitable for coatings with substrates with an atomic number greater. The capacitance method is only used when thickness measurement is applied to the insulating coating of a thin conductor.

With the advancement of technology, especially after the introduction of microcomputer technology in recent years, the thickness gauges using magnetic method and eddy current method have taken a step toward micro, intelligent, multifunctional, high-precision and practical. The resolution of the measurement has reached 0.1 micron, and the precision can reach 1%, which has been greatly improved. It has a wide range of applications, wide measuring range, easy operation and low cost. It is the most widely used for thickness measuring instrument in the industrial and scientific research.