The roughness of a surface is a morphological characteristic. It has a unit of length which corresponds to the characteristic depth of the ridges furrowing its surface.
Some examples of roughness of common materials
The table below shows some average roughness values for everyday materials:
|polished mirror||0-1 micron|
|planed wood||10-20 microns|
|bare steel||50-100 microns|
|Gross cement||1000 microns|
How is roughness measured?
The roughness is determined by calculation from surface profiles measured by 2D or 3D optical profilometry.