![© Max-Planck-Institut für Eisenforschung GmbH © Max-Planck-Institut für Eisenforschung GmbH](/3036562/header_image-1456238058.jpg?t=eyJ3aWR0aCI6ODQ4LCJmaWxlX2V4dGVuc2lvbiI6ImpwZyIsIm9ial9pZCI6MzAzNjU2Mn0%3D--1a43f7196914961dcd01b6439d0cff0dbf14fa28)
Nanotribology: Size-dependent friction coefficient and surface evolution
Wear and abrasion occur during sliding friction of metallic body and counter-body. Surface roughness is purposefully introduced into the metal to reduce wear and abrasion and to increase the lubricant flow.
As both bodies slide past each other, solid - solid micro-contacts develop because the lubricant only partially covers the surface in most applications.
![Wear track in austenitic stainless steel and plasticity evolution depending on the crystal orientation](/3742220/original-1518437874.jpg?t=eyJ3aWR0aCI6MjQ2LCJvYmpfaWQiOjM3NDIyMjB9--c854dcef13eb8d0a25dba762da4751e8be35502d)
Wear track in austenitic stainless steel and plasticity evolution depending on the crystal orientation
To mimic the micro-contacts and the plastic micro-plowing during run-in, we use a diamond sphere as counter-body for the studied metals. During the deformation process, forces and displacements in the normal and tangential direction are recorded and this time-dependent data is analyzed using spectral analysis. Post-deformation measurements of the surface roughness by atom force microscopy (AFM) and confocal microscopy allow to determine the real contact area and the traces of the metal stick-slip behavior.
Images from the scanning electron microscope (SEM) show the microstructure evolution.