Measurement method for coating thickness

The measurement of paint film thickness is a difficult technical problem to solve, and the measurement of coating thickness has become an important part of quality inspection in the processing industry and surface engineering. It is a necessary means for products to achieve excellent quality standards.

The measurement methods for coating thickness mainly include wedge cutting method, light cutting method, electrolysis method, thickness difference measurement method, weighing method, X-ray fluorescence method, β X-ray backscatter method, capacitance method, magnetic measurement method, eddy current measurement method, etc.

The first five of these methods are lossy detection, with cumbersome measurement methods and slow speed, and are mostly suitable for sampling inspection.

With the increasing progress of technology, especially in recent years, with the introduction of microcomputer technology, the use of magnetic and eddy current methods in paint film thickness gauges has taken a step towards miniaturization, intelligence, multifunctionality, high precision, and practicality.

The resolution of the measurement has reached 0.1 micrometers, and the accuracy can reach 1%, with a significant improvement.

A paint film thickness gauge using the principle of magnetic induction can, in principle, have a non magnetic coating thickness on a magnetic substrate. Eddy current thickness gauge is a high-frequency AC signal that generates an electromagnetic field in the coil of the measuring head. When the measuring head is close to the conductor, eddy currents are formed within it.

The closer the probe is to the conductive substrate, the greater the eddy current and reflection impedance. This feedback action characterizes the distance between the probe and the conductive substrate, which is the thickness of the non-conductive coating on the conductive substrate.

The paint film thickness gauge is not only fast and accurate, but also relatively stable. The accuracy and stability of the paint film thickness gauge are not lower than similar foreign products, in order to make the product international;

In China's export commodities and foreign-related projects, there are clear requirements for production, and regular inspections are carried out in accordance with national requirements to ensure their quality and meet customer requirements.