ABSTRACT
The first friction model was the Coulomb model, which states that the friction
coefficient is constant. Recall that the friction coefficient is the ratio
f ¼ Ff F
ð16-1Þ
where Ff is the friction force in the direction tangential to the sliding contact
plane and F is the load in the direction normal to the contact plane. Discussion of
the friction coefficient for various material combinations is found in Chapter 11.
