Compensating for elastic deformation of the indenter in hardness tests of very hard materials
- 1 June 1999
- journal article
- Published by Springer Science and Business Media LLC in Journal of Materials Research
- Vol. 14 (6), 2276-2282
- https://doi.org/10.1557/jmr.1999.0304
Abstract
The current method of analysis for hardness measurements by indentation is examined. Although the method is based on Sneddon's solution for an elastic stress field within a homogeneous half space indented by an elastically deformable indenter, it implicitly assumes a fixed indenter geometry. Therefore, if indentations are made on materials whose hardness or elastic modulus are close to those of the indenter, this method underestimates the contact area and, thus, overestimates the hardness and modulus values of the indented materials. A new method, based on the Hertz contact theory, is proposed that accounts for the elastic deformation of the indenter and provides a simple way to calculate the tip radius. The restrictions of this method are also indicated and discussed. Finally, the hardness and modulus for two recently developed films are measured by this method, and the results are compared with published finite element method (FEM) results.Keywords
This publication has 8 references indexed in Scilit:
- Synthesis and characterization of thin films of WCx produced by mixing W and C plasma streamsSurface and Coatings Technology, 1997
- Finite-element modeling of nanoindentation for determining the mechanical properties of implanted layers and thin filmsNuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 1997
- Hardness, elastic modulus, and structure of very hard carbon films produced by cathodic-arc deposition with substrate pulse biasingApplied Physics Letters, 1996
- Nanoindentation Hardness Tests Using a Point Contact MicroscopeJournal of Tribology, 1994
- On the generality of the relationship among contact stiffness, contact area, and elastic modulus during indentationJournal of Materials Research, 1992
- Contact MechanicsJournal of Tribology, 1986
- Contact MechanicsPublished by Cambridge University Press (CUP) ,1985
- The relation between load and penetration in the axisymmetric boussinesq problem for a punch of arbitrary profileInternational Journal of Engineering Science, 1965