Despite the great importance of the real contact area, it is a parameter which, depending
on the tribological system, is difficult or impossible to obtain experimentally. In this
work, a combination of methods was used to estimate the development of the real
contact surface, and the results were compared with the friction coefficient course. The
measurements were carried out with a home-built in situ tribometer, which records a
3D image of the surface after each individual friction cycle. A tungsten sample was
treated by laser interference with a line-like pattern to produce a deterministic surface.
This allowed for more precise tracking of the real contact area when combined with the
use of an inert corundum sphere as a counter-body. The real contact area was calculated
numerically from the height information obtained using a contact application. Finally, the
true contact surface was compared with the parallel-recorded friction values. After a short
running-in phase, the friction behavior and the real contact surface showed comparable
courses. This indicates that the changes in the real contact area could explain the fr ... mehriction
behavior of the laser-patterned sample, and the methodology was proven to be suitable
for experimentally estimating the real contact area.