Characterisation of coatings with metallographic methods
The present technical equipment allows the preparation of metallographic specimen and the destructive testing and characterising of coatings visible in an optical microscope (layer thickness ≥ 2 µm).
Beginning with the sampling point, to be continued by cold- and warm embeding procedures with various resins (epoxy-, phenol- and acrylic resins) and closing with corresponding grinding- and polishing steps obtain the metallographic specimen that can be characterised.
The characterisation is carried out by an inverse optical microscope "Axiovert 25C" (Carl Zeiss Jena GmbH).
Following tasks can be processed:
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Classical metallographic micrograph, -constituent investigation
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Investigation procedure for fibre-reinforced materials (fibre orientation, fibre volume, matrixbonding)
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Determination of the filling degree from reinforced polymers
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Picture processing and -documentation
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Layer thickness determination by lateral cut examination down to 2 µm
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Pyramid diamond hardness determination µ-HV (F ≤ 1N) on coatings and constituents
The optical microscope can be utilised in three different contrast modes up to 1000-times magnified. Bright field microscopy, dark field microscopy and differential interference contrast microscopy (DIC) with inversed impinging light.
Measurement of the layer thickness on a black plasmachemical oxidised titanium workpiece
Microhardness on a cross sectional area of a capillary tube
Liability case analysis of a ABS-casting workpiece
Lacquer structure of an aluminium workpiece
Aluminised stainless steel (Al - layer thickness)