Coating thickness gauge is mainly used to measure the thickness of coatings (such as coatings, coatings, coatings, etc.) on the surface of metal substrates. It is widely used in manufacturing, metal processing, chemical industry and other fields, and is a key testing equipment to ensure product quality meets standards. Non destructive testing is achieved through X-ray fluorescence spectroscopy analysis technology or electromagnetic induction principle, supporting micrometer level precision measurement, and can analyze the structure and elemental composition of multi-layer coatings.
Coating thickness gauge is an instrument used to measure the thickness of coatings or coatings on metal or non-metal substrates. Its working principle is mainly based on electromagnetic induction method, eddy current method or X-ray fluorescence method. Here are several common working principles:
Electromagnetic induction method: suitable for measuring non-magnetic coatings on magnetic substrates. The instrument generates an alternating magnetic field through the probe, and the magnetic permeability of the substrate affects the changes in the magnetic field. The coating thickness is calculated by measuring the changes in the magnetic field.
Eddy current method: suitable for measuring non-conductive coatings on non-magnetic substrates. The probe generates a high-frequency alternating magnetic field, inducing eddy currents in the substrate. The intensity of the eddy currents is related to the thickness of the coating, and the thickness is determined by measuring the changes in the eddy currents.
X-ray fluorescence method: suitable for measuring multi-layer coatings or alloy coatings. The instrument emits X-rays, and the elements in the coating absorb and emit fluorescence. The thickness of the coating is calculated by analyzing the fluorescence intensity.
The maintenance of the coating thickness gauge should focus on instrument cleaning, calibration, environmental management, and daily inspections. The specific points are as follows:
Instrument cleaning and calibration
Surface treatment: Before measurement, the surface of the specimen must be cleaned to remove oil stains, oxide layers, and dust, in order to avoid contamination that may interfere with measurement accuracy. It is recommended to use anhydrous ethanol and a dust-free cloth for wiping. Stubborn stains can be lightly scraped with a plastic scraper with a hardness of ≤ 2H. It is forbidden to use metal tools to avoid scratching the substrate.
Calibration process: Before each measurement, a calibration plate (such as an iron-based galvanized calibration plate) is required for zero point calibration and multi-point calibration to ensure that the calibration value is within the error range. When measuring the curved surface, it is necessary to select three calibration points through the laser positioning function of the instrument to ensure that the vertical deviation between the measuring head and the surface of the specimen is less than 5 °.
Storage environment: Avoid damp, high temperature or strong magnetic field environment, and prevent corrosive gases/liquids from contacting the instrument. When not in use for a long time, remove the battery and turn off the power to keep the instrument dry.