Coating thickness by Calotest
The Calotest provides quick, simple and inexpensive determination of coating thicknesses. A rotating sphere, with a known diameter (Ø ball) is pressed on the coating surface with a preselected load. Both the position of the sphere relative to the sample and the contact load are constant. Upon adding abrasive slurry to the contact zone, a depression with the shape of a spherical cap is abraded into both the coating and the substrate.
Optical inspection of the depression reveals the projected surfaces of the abraded coating and substrate sections. By measuring the parameters X and Y, the thickness of the coating D can be calcuted by a simple geometrical equation.
The Calowear system extends the Calotest principle by incorprating a force sensor, a revolution counter and an automated slurry dispenser. A steel ball rolls on the test sample and a slurry composed of water and SiC particles falls continuously onto the ball at the contact region. The slurry wears the substrate in a controlled manner and thus assures highly reproducible results.
> Spherical abrasion test method
|Application Bulletin n°37||
Physical characterization of coated surfaces - Part I : Instrumented Indentation
|Application Bulletin n°09||
- MST Swinging Module for variable frequency scratch testing
|Application Bulletin n°08||
- New Industrial Calotest for improved coating thickness determination
|Application Bulletin n°05||
- Finer particle size allows better coating characterization with the Calotest
|Application Bulletin n°03||
- New integrated SFM objective for better characterization of NHT indentations