Dynamic Friction of Nano-Materials
Abstract
Pressure-shear plate impact friction experiments, Prakash et al., 1993, Espinosa et al., 1997, were introduced to study time-resolved friction at sliding interfaces. This configuration offers the simplicity of allowing the interpretation of the experimental results by using the framework of plane wave analysis. The experiments are conducted to simulate the local conditions of pressure and sliding velocity that can occur in high speed machining and ballistic penetration. A modified Split-Hopkinson (Kolsky) bar method consisting in the dynamic loading in shear of a pre-compressed thick-wall sample has been developed. The technique allows the identification of the transient response from static to kinetic friction under sliding velocities of about 2-6 m/s. The normal and tangential forces are measured independently and hence a dynamic friction coefficient identified. The sliding velocities obtained with the Kolsky bar are smaller than those obtained in pressure-shear friction experiments. Hence, the techniques are complementary and provide value information for the formulation of friction laws at sliding velocities, pressures and temperatures typical of manufacturing processes.
- Publication:
-
APS Shock Compression of Condensed Matter Meeting Abstracts
- Pub Date:
- June 1999
- Bibcode:
- 1999APS..SHK..K304Z