Abstract
We revisit the scratch test within the framework of linear elastic fracture mechanics. In the analysis, we employ an Airy stress function approach to determine stresses and displacement in the vicinity of the scratch-blade-material interface, which serve as input for the evaluation of the energy release rate by means of the J-Integral. In contrast to previous models, the energy release rate thus found scales with the sum of the applied forces squared. This entails a linear relation between the applied forces and w√d, where w is the scratch width and d the scratch depth. This analytical scaling is validated using experimental scratch data on cement paste and sandstone, which shows that the proposed approach provides a convenient way to determine the fracture toughness from scratch tests carried out with different scratch widths and depths.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 334-342 |
| Number of pages | 9 |
| Journal | Engineering Fracture Mechanics |
| Volume | 78 |
| Issue number | 2 |
| DOIs | |
| State | Published - Jan 2011 |
Funding
The authors gratefully acknowledge the financial support of this study by the Total scholarship for graduate studies of ATA at MIT, and by discretionary funds of the George Macomber Chair for FJU at MIT. The experimental scratch data for cement paste are courtesy of Schlumberger Carbon Services, and the scratch data on red sandstone courtesy of Epslog Engineering SA, Belgium. A special thanks to Dr. Brice Lecampion (Schlumberger), Dr. Christophe Germay (Epslog Engineering SA) for the experimental data, to Romain Bard (MIT) for contributing the Finite Element result, and to Prof. David Parks (MIT) for fruitful discussions.
Keywords
- Fracture toughness
- J-Integral
- Scratch test
ASJC Scopus subject areas
- General Materials Science
- Mechanics of Materials
- Mechanical Engineering