With a coating thickness measuring device, you can measure the thickness of coatings on surfaces. Whether paint or lacquer, whether plastic, whether an anodized layer, whether galvanic coating - it is important that the layer is applied firmly and dry to the base material. With a coating thickness measuring device you can measure a single coating or a multiple coating (color on zinc on steel).
Coating thickness measurement of paint takes place during quality assurance in the painting process in order to monitor the optimal use of materials. Experts check whether metal parts are adequately protected against corrosion by paint: on vehicles, steel girders, railings. Zinc plating or chrome plating are further areas of application for a coating thickness measuring device.
Non-destructive layer thickness measurement
The layer thickness measurement with devices from List-Magnetik is non-destructive. The device is put on gently and does not damage a dried coating.
The unit used in coating thickness measurement is µm or micron. A µm is a thousandth of a millimeter. A measurement accuracy of 1 µm can be achieved in the range below 100 µm.
Substrate required for layer thickness measurements: Metal - "FE" metals and "NFE" metals
The most important requirement for the layer thickness measurement with devices from List-Magnetik: There is a metallic background. A coating thickness measurement over ceramics, glass or plastic is not possible with our coating thickness measuring devices.
Coating thickness measurement for magnetizable metals
Ferromagnetic metals (FE metals for short) such as steel, iron and cobalt can be magnetized. They can be measured magnetically inductive. Nickel is normally also ferromagnetic, but not if the phosphorus content is 11% or more.
Coating thickness measurement for non-magnetizable metals
"Non-ferromagnetic" NFE metals are all other metals that are electrically conductive. The eddy current method is used here. For example, with aluminum, copper or zinc. Stainless steel can be slightly ferromagnetic, but like an NFE metal, it should be measured using the eddy current method.
Magnetic induction either generates a magnetic field with a tiny permanent magnet, the strength of which is then measured with a Hall sensor. The thicker the layer, the lower the attenuation of the measurement signal. The thickness can be derived from this. In the eddy current process, an alternating magnetic field generates eddy currents in the base material, the resonance of which can be converted into layer thickness.
A wide selection of probes for professional coating thickness measurement
Most applications can be covered with a standard probe. The paint layer on vehicles or buildings, or anodized aluminum housing.
However, if you need to determine the layer thickness in recesses or pipes, on a small area, under steel beams or at measuring points that are difficult to reach, special probes and applications are available.
In this way, the TOP-CHECK measuring device can swivel its probe by 90°. Tangential probes measure inside pipes. The interior of boilers can be reached with telescopic rods.
What's your challenge? We would be happy to advise you on your application.
Measurement of layer thicknesses in multi-layer structures - galvanizing plus painting
In the case of multi-layer structures, two layers can be measured separately from one another if the substrate is ferromagnetic, the first layer above the substrate is metallic and non-ferromagnetic, and the top layer is non-conductive. For example, a galvanized and then painted sheet steel.
In the case of a single measurement, the layer thickness of the paint and the galvanizing are shown separately. The MEGA-CHECK Master coating thickness measuring device offers the duplex mode for this purpose.
Layer thickness measurement on a rough layer or on a rough surface
As a rule, the minimum value is important for rough layers. Therefore, measurements must be made at several points in order to determine the minimum. It is important to capture the “mountains” and “valleys” of the layer without any gaps. With the scan mode of the coating thickness measuring device MEGA-CHECK Master you move the probe over the surface, recognize the change and automatically determine the extreme values.
Calibrate a coating thickness meter
To calibrate a coating thickness measuring device, you need a bare metal plate and a defined calibration foil. In the first step you carry out a zero calibration without foil on the bare plate. In the second step, repeat the process, but with the foil between the plate and the probe. You have now carried out a two-point calibration which has programmed a stable characteristic curve into the device. You can check the characteristic curve with another control film.
For devices with a combined probe, this calibration must be carried out once for the FE measurement and once for the NFE measurement.
Our video shows the calibration of a TOP-CHECK coating thickness meter.
Calibration material for the coating thickness measuring device
For the best result, it is best to have an uncoated area of the same geometry on the same material that you want to test the coating. Then the chemical composition of the material and its geometry, whether round or concave, match the measuring environment perfectly. If that is not possible, simply use our calibration plates supplied.
We deliver everything you need. The "blue" plate is made of steel, the "red" plate is made of aluminum. With the 300 µm calibration film, the optimum characteristic curve can be achieved for layers up to 2 mm. In the case of significantly thicker layers, we recommend calibration with a 1 mm thick ceramic plate instead of the foil.
Transfer data from the coating thickness meter to the PC or app
Do you need to document or archive your series of measurements? Would you like to recognize extreme values and carry out statistical evaluations? Are you measuring at a point where you cannot even see the display of the coating thickness measuring device? Then our TOP-CHECK BLE App for Android / iOS and PC applications are the right tools.
The Android app can also be used for voice output of online measurements if you neither have your coating thickness measuring device nor your mobile smartphone or tablet in view.
The applications enable measurement series to be further processed or integrated in Office applications. Integration into CAQ systems is also possible.
Measuring instruments by List-Magnetik - Made in Germany - Quality and durability