Abstract
Designing thin-film coatings to meet engineering needs requires the knowledge of accurate mechanical properties of the coatings. Young's modulus and Poisson's ratio are two basic mechanical properties of materials, which should be conveniently measured. This paper reports a direct and non-destructive method for the measurement of the Young's modulus and Poisson's ratio of a thin-film coating and its substrate based on the extended Hertz theory for the contact of coated bodies. The theory is used to analyze load-displacement data from a spherical indentation in the elastic range, in which the substrate effect is intrinsically modeled. The Young's modulus and Poisson's ratio are determined at the same time through minimizing the difference between the measured and specially defined modified Young's moduli. Two sets of validation experiments are also reported. This new method does not require any assumptions on pressure distribution and Poisson's ratio and can be easily incorporated into current indentation analysis systems.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 6470-6477 |
| Number of pages | 8 |
| Journal | Surface and Coatings Technology |
| Volume | 201 |
| Issue number | 14 |
| DOIs | |
| State | Published - Feb 4 2007 |
Funding
The authors would like to express their sincere gratitude to the support from US Office of Naval Research and National Science Foundation. They would also like to thank Dr. M. Hans at Balzers, Inc. for TiN coating deposition and thickness measurement and Dr. E.G. Herbert at MTS and Mr. Yanfeng Chen at Northwestern University for nanoindentation testing.
Keywords
- Measurement
- Nanoindentation
- Poisson's ratio
- Thin-film coating
- Young's modulus
ASJC Scopus subject areas
- General Chemistry
- Condensed Matter Physics
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Materials Chemistry