Surface modification is a promising method to solve the tribological problems in microsystems. To modify the surface, we fabricated hierarchical patterns with different pitches of nano-scale features and different surface chemistries. Micro- and nano-patterns with similar geometrical configurations were also fabricated for comparison. The nano-tribological behavior of the patterns was investiga...

This experimental work is oriented to give a contribution to the knowledge of the relationship among surface roughness parameters and tribological properties of lubricated surfaces; it is well known that these surface properties are strictly related, but a complete comprehension of such correlations is still far to be reached. For this purpose, a mechanical polishing procedure was optimized in ...

Acoustic phonon transport is revealed as a potential radiation-to-conduction transition mechanism for single-digit nanometer vacuum gaps. To show this, we measure heat transfer from feedback-controlled platinum nanoheater to laterally oscillating silicon tip the tip-nanoheater gap distance precisely controlled down bulk contact in high-vacuum shear force microscope. The measured thermal conduct...

Fracture asperities interlock or break during stick slip and ride over each other stable sliding. The evolution of fracture the transition between sliding has attracted less attention, but is important to predict behaviour. Here, we conduct a series direct shear experiments on simulated fractures in homogeneous polycarbonate examine stage. Our results show that stage occurs stages progressive r...

While sliding at seismic slip-rates of ?1 m/s, natural faults undergo an abrupt decrease shear stress called dynamic weakening. Asperity-scale (<<mm) processes related to flash heating and weakening and, meso-scale (mm-cm) involving across the bulk slip-zone, frictional melting or viscous flow minerals, have been invoked explain pronounced velocity-dependent Here we present a compilation ?100 e...