Non-Destructive Testing Methods and Principles of Coating Thickness Gauges
The non-destructive testing method and principle of coating thickness gauge: Coating thickness gauge is a promising discipline with strong theoretical comprehensiveness and great emphasis on practical aspects in practical measurement. It involves many aspects such as the physical properties of materials, product design, manufacturing processes, fracture mechanics, and finite element calculations.
In industries such as chemical, electronic, power, and metal, in order to achieve protective or decorative effects on various materials, methods such as spraying non-ferrous metal coatings and phosphating, anodizing, etc. are usually used. This has led to the emergence of concepts such as coatings, plating layers, coatings, stickers, or chemically generated films, which we call "coatings".
The measurement of coating thickness has become an essential process for quality inspection of finished products in the metal processing industry. It is an essential means for products to meet * * standards. At present, the thickness of coating layers is generally measured according to unified international standards both domestically and internationally. The selection of non-destructive testing methods and instruments for coating layers has become increasingly crucial with the gradual progress of material physical property research.
Regarding non-destructive testing methods for coatings, there are mainly wedge cutting method, light cutting method, electrolysis method, thickness difference measurement method, weighing method, X-ray fluorescence method, beta ray reflection method, capacitance method, magnetic measurement method, and eddy current measurement method. Except for the last five methods, most of these methods require damage to the product or its surface, which is a form of damage detection. The measurement methods are cumbersome and slow, and are mostly suitable for sampling inspection.
The X-ray and beta ray reflection methods can be used for non-contact and non-destructive measurement, but the equipment is complex and expensive, and the measurement range is small. Due to the presence of radioactive sources, users must comply with radiation protection regulations, which are generally used for thickness measurement of various metal coatings.
