The detection principle of the eddy current coating thickness gauge
Coating thickness gauge is a professional measuring instrument for detecting the thickness of coating or coating, so it can also be called coating thickness gauge. The coating thickness gauge produced by Jining Aotai is professional for detecting coating or The thickness of the coating is specifically divided into magnetic thickness measurement for detecting the coating thickness on the magnetic metal surface (such as the coating thickness of zinc, copper, chromium, etc. Thickness gauges, and thickness gauges for coating thickness on non-magnetic metals (such as paint on non-ferrous metals, paint on aluminum substrates, or oxide films, etc.), this type of thickness gauge for detecting the thickness of non-magnetic metal coatings is what we often say The eddy current thickness gauge, which uses the eddy current thickness measurement method for thickness detection, and today we will talk about the principle of the eddy current thickness gauge.
Compared with the magnetic induction principle, the eddy current thickness gauge mainly differs in the measuring probe, and the non-magnetic probe uses high-frequency material as the coil core. When the high-frequency AC signal generates an electromagnetic field in the probe coil, when the probe is close to the conductor, eddy currents are formed in it. The closer the probe is to the conductive substrate, the greater the eddy current and the greater the reflection impedance. This feedback action characterizes the size of the distance between the probe and the conductive substrate, that is, the thickness of the non-conductive coating on the conductive substrate. Because this type of coating thickness gauge probe is designed to measure the thickness of coatings on non-ferromagnetic metal substrates, it is often called a non-magnetic probe. The eddy current thickness gauge, in principle, can measure non-conductive coatings on all conductive substrates, such as paints, plastic coatings and anodized films on the surfaces of aerospace vehicles, vehicles, home appliances, aluminum alloy doors and windows and other aluminum products.
