Coating Characterization

Coating thickness evaluation on a carbon coating with complex interlayer architeecture, using crater-grinding method.
© Fraunhofer IWS
Coating thickness evaluation on a carbon coating with complex interlayer architeecture, using crater-grinding method.
Stress analysis on a multi-layer coating.
© Fraunhofer IWS
Stress analysis on a multi-layer coating.
Detailed examinations following the scratch test provide insights into adhesive and cohesive failure.
© Fraunhofer IWS
Detailed examinations following the scratch test provide insights into adhesive and cohesive failure.

For the development and application of suitable coating systems, precise and reproducible determination of the relevant key characteristics is required. In addition to standard methods, specially developed procedures are used, for which there is a deep methodological understanding. The scope of characterization also includes tribological investigations (Group Tribological Systems) and laser-ultrasonic methods (LAwave®).

 

Range of Services

We Offer:

  • Characterization of CVD and PVD coatings
  • Characterization of thermally sprayed and laser-cladded layers
  • Special expertise for superhard amorphous carbon coatings (ta-C)
  • Contact-mechanical application analyses for properly dimensioned experimental de-sign
  • Failure analysis
  • Consulting and development of quality assurance concepts

We Investigate:

Hardness and Young’s modulus (E-modulus), adhesion, friction and wear, coating thickness, residual stress, roughness (2D, 3D), metrological surface defect analysis, bonding structure (e.g., sp3 content), microstructure, chemical composition, density 
 

For this We Employ: 

  • Scratch test with applied force ranges up to 2, 30, and 100 N
  • Instrumented hardness testing with force ranges 0.01…2 N and 0.1…10 N at temperatures up to 400 °C
  • Various indenter shapes and radii, tailored to the specific question
  • Laser-ultrasonic surface-wave spectroscopy (LAwave®)
  • Tactile and optical profilometry for deflec-tion and roughness measurement
  • Calotte grinding process
  • Raman spectroscopy
  • Software for contact-mechanical simulation (FilmDoctor)
  • Microscopy: SEM/EDX, TEM, light micros-copy, 3D (confocal, interferometric)
  • Tribometer: rotating/oscillating model body or axial-glide bearing; temperature -5…350 °C; surrounding medium dry, controlled atmosphere, lubricated or vacuum

Thanks to interdisciplinary collaboration, the expertise and test capabilities of the Materials Characterization and Testing competence field and other business areas at Fraunhofer IWS are also available. We would be happy to advise you on this. 

Scientific Focus

Investigation of damage tolerance of coatings using indenter experiments.
© Fraunhofer IWS
Investigation of damage tolerance of coatings using indenter experiments.
  • Quantification and evaluation of particle coverage on PVD coatings
  • Simulation and experimental investigations of contact-mechanical loading cases (Indentation, Ritz test, Pop-In), and the resulting optimization of coating systems
  • Experimental assessment of the damage tolerance of hard coating systems
  • Methodology for quantifiability and scalability of adhesion strength through single supercritical or cyclic subcritical loading, including the concept of the delaminated area
  • Methodological extension of instrumented indentation testing (nanoindentation) for superhard coatings, including the influence of the evaluation model and depth-resolved measurement
  • Raman spectroscopy on carbon-containing layers to determine structure and its changes due to doping, temperature exposure, or tribological loading
  • Further development of laser-ultrasonic testing methods (LAwave®) for established and new applications
  • Investigations of special tribological properties of amorphous carbon coatings, such as superlubricity, behavior with renewable lubricants, and tribochemical wear mechanisms, screening of lubricants and coatings
  • Testing at elevated temperatures: nanoindentation and nanoscratch testing up to 400 °C; measurement of Young’s modulus, density, or layer thickness using LAwave at temperatures up to 600 °C

Highlights and Scientific Experise

 

Tribology Innovation Center Dresden (TICD)

Tribological coatings and surface modifications – expertise in friction reduction and wear protection

Publications

Get an insight into the current publications of Fraunhofer IWS on coating characterization.

Press and Media

 

Press Release / 27.3.2024

The Sound of the Perfect Coating

Fraunhofer IWS Transfers Laser-based Sound Analysis of Surfaces into Industrial Practice with “LAwave”

 

Press Release / 12.10.2021

Superlubricity Eliminates Friction in Engines

Fraunhofer IWS Works on Machines that Barely Lose Energy in the Form of Waste Heat

 

News / 24.3.2021

Non-destructive Coating Analysis on Brake Discs with LAwave® Technology