What Is an Electromagnetic Coating Thickness Gauge?
An electromagnetic coating thickness gauge is a device that measures the thickness of a thin film using the principle of electromagnetic induction.
The thickness can be measured by placing a coil close to the measurement area and measuring minute inductive electromotive forces. It measures the thickness of thin films and coatings that cannot be measured with calipers, etc. There are other types of film thickness gauges, such as eddy current, ultrasonic and reflectance spectroscopy, and it is important to select the right one depending on the object to be measured.
While electromagnetic coating thickness gauges can instantly and accurately measure thickness, they have the disadvantage that they cannot measure well if the thin film is magnetic.
Uses of Electromagnetic Coating Thickness Gauges
1. Metal Industry
Electromagnetic coating thickness gauges are widely used in the metal product manufacturing industry. The measurement of metal film thickness enables product quality control and optimisation of the manufacturing process. For example, in the automotive industry, to ensure paint uniformity and durability.
2. The Construction Industry
In the building industry, electromagnetic coating thickness gauges are used to measure the thickness of coatings and paints applied to concrete and steel surfaces. This ensures the durability and visual quality of buildings.
3. Corrosion Monitoring
Corrosion monitoring is used to monitor the corrosion state of metal products and structures. As the film thickness decreases as corrosion progresses, regular measurements enable the progress of corrosion to be monitored and the necessary protective measures to be taken.
4. Electronics Industry
Electromagnetic coating thickness gauges are used to measure the film thickness on the surface of minute components such as electronic components and printed circuit boards. This is essential to ensure the performance and reliability of components.
5. Chemical Industry
In chemical processes, electromagnetic coating thickness gauges are used to control and monitor the film thickness of chemical and coating materials. They contribute to improved product quality and process optimisation.
6. Aerospace Industry
Uniformity of film thickness and accurate dimensions are important for aircraft and space equipment components. Electromagnetic coating thickness gauges are an essential tool in the manufacture and maintenance of these components.
Principle of Electromagnetic Coating Thickness Gauge
The structure consists of a probe containing an electromagnet, which is brought into contact with the surface to be measured. When an electric current is applied to the electromagnet, electromagnetic induction occurs, attracting the magnetic material behind the thin film. The voltage of the coil changes according to the distance between the electromagnet and the magnetic material, and this is used to measure the film thickness.
Like calipers, it does not need to be clamped from both sides and can measure minute thicknesses that cannot be measured by eye. In addition, electromagnetic coating thickness gauges can instantly and accurately measure thickness, and are easy to operate and can be handled by anyone.
Thickness can only be measured when the substrate is magnetic, such as a metal, and the object to be measured is non-magnetic. Examples include non-magnetic metal plating, paint and resin coatings. On the other hand, if the film thickness is under a non-magnetic object or if the object has an uneven surface, it cannot be measured accurately because the electromagnet must be in close contact with the surface.
How to Select an Electromagnetic Coating Thickness Gauge
1. Intended Use
First of all, it is necessary to clarify for which application the electromagnetic coating thickness gauge is to be used. There are different types to suit different applications, e.g. for measuring the thickness of metal coatings, measuring the thickness of coatings, monitoring corrosion, etc. 2.
2. Accuracy and Resolution
If measurement accuracy is important, it is essential to choose a high-precision electromagnetic coating thickness gauge. It is also important to take resolution into account. The required accuracy and resolution depend on the intended use and application, so the application must first be determined.
3. The Type of Material
It is important to select the right electromagnetic coating thickness gauge for the material being measured. The suitable electromagnetic coating thickness gauge depends on the material of the object, e.g. metallic, non-metallic or coated materials.
4. Measuring Range
Consider the range of coating thicknesses to be measured and whether the range can be covered. There are various options available, ranging from wide to narrow ranges. If the range cannot be foreseen in advance, electromagnetic coating thickness gauges that can measure as wide a range as possible should also be considered.
5. Ease of Operation
The ease of use of electromagnetic coating thickness gauges is also a factor to be considered. An intuitive interface and easy-to-use software will help to ensure efficient measurement operations. As detailed work may be required, it is important to take into account the time required for operation.
6. Durability and Maintenance
To maintain stable performance over a long period of time, it is necessary to select durable products. Regular maintenance and calibration are also important, so it must be ensured that they can be easily performed.