Friction and wear in light of elastic interactions between micro contacts
Event details
| Date | 17.02.2022 |
| Hour | 16:00 › 17:00 |
| Speaker | Prof. Jean-François Molinari Computational Solid Mechanics Laboratory, Civil Engineering Institute, Materials Science Institute, EPFL Lausanne |
| Location | Online |
| Category | Conferences - Seminars |
| Event Language | English |
Abstract: It is well known that man-made and natural surfaces are rough, with roughness observed over many length scales. An important consequence is that the real contact area is much smaller than the nominal contact area, and is made of micro contacts that vary in size and shape. It is well known that elastic interactions between nearby micro contacts matter. Elastic interactions are felt over long distances, affect the location and average size of micro contacts, and influence the tribological properties. In particular, in the case of adhesive and abrasive wear, we show how crack shielding mechanisms between nearby asperities promote the formation of larger debris, thereby providing a mechanistic understanding of the transition for mild to severe wear at a critical load.
While these results were initially observed through molecular dynamics simulations, we will discuss our recent efforts at generalizing those early observations with computationally efficient continuum solvers, through the boundary-element method or the finite-element method incorporating phase-field modeling of fracture.
Ultimately, elastic interactions help revise the definition of a contact asperity, by incorporating nearby contact junctions into an effective contact area. The presentation will also explore optimization strategies in order to maximize elastic interactions for more efficient grip or scraping tools technology.
While these results were initially observed through molecular dynamics simulations, we will discuss our recent efforts at generalizing those early observations with computationally efficient continuum solvers, through the boundary-element method or the finite-element method incorporating phase-field modeling of fracture.
Ultimately, elastic interactions help revise the definition of a contact asperity, by incorporating nearby contact junctions into an effective contact area. The presentation will also explore optimization strategies in order to maximize elastic interactions for more efficient grip or scraping tools technology.
Practical information
- General public
- Registration required
Organizer
- EPFL : Prof. John Kolinski, [email protected] ETHZ : Prof. George Haller, [email protected]