COLL 62 |
| George G. Adams and Sinan Muftu. Mechanical Engineering, 334 SN, Northeastern University, 360 Huntington Avenue, Boston, MA 02115 |
| As loading forces decrease in applications such as MEMS and NEMS devices, the size of the asperity contacts which comprise the real contact area tend to decrease into the nano-scale regime. A multi-asperity model for contact and friction is developed by combining the single asperity nano contact model of Hurtado and Kim with the effect of asperity adhesion forces using the Maugis-Dugdale model. The resulting model spans the range from nano-scale to micro-scale to macro-scale contacts and includes the effect of asymmetric asperity height distributions. Three key dimensionless parameters are identified representing certain combinations of surface roughness measures, Burgers vector length, surface energy, and elastic properties. Results are given for the friction coefficient vs. normal force, the normal and friction forces vs. separation, and the pull-off force for various values of these key parameters and of the skew/kurtosis of the asperity height distribution. |
|
Friction, Lubrication, and Adhesion in Micro- and Nano-Scale Devices
2:00 PM-5:00 PM, Sunday, March 28, 2004 Marriott -- Orange County 5, Oral
Division of Colloid and Surface Chemistry |