Extreme care is needed in using friction coefficients and additional
independent references should be used.
For any specific application the ideal method
of determining the coefficient of friction
is by trials. A short table is
included above the main table to illustrate
how the coefficient of friction is affected
by surface films. When a metal
surface is perfectly clean in a vacuum . the
friction is much higher than the normal accepted
value and seizure can easily occur.
of Oxide film, Sulfide film
on Coefficient of Static Friction