The exact contact between two rough surfaces is usually estimated using statistical
mathematics and surface analysis before and after contact has occurred. To date the majority
of real contact and loaded surfaces has been theoretical or by numerical analyses. A method
of analysing real contact area under various loads, by utilizing a con-contact laser surface
profiler, allows direct measurement of contact area and deformation in terms of contact force
and plane displacement between two surfaces. A laser performs a scan through a transparent
flat side supported in a fixed position above the base. A test contact, mounted atop a spring
and force sensor, and a screw support which moves into contact with the transparent surface.
This paper presents the analysis of real contact area of various surfaces under various loads.
The surfaces analysed are a pair of Au coated hemispherical contacts, one is a used Au to Au
coated multi-walled carbon nanotubes surface, from a MEMS relay application, the other a
new contact surface of the same configuration.