Coefficient of Friction Change with Heat
Country: United States
Date: November 2008
Why brake pads, when pressed against a steel drum,
loose friction at very high temperatures?
There are probably a number of causes, but an important one is that the steel
drum "polishes" the brake pad, so that the friction between the two components
is less. The ability to stop depends upon converting the kinetic energy of the
vehicle into heat. Heat between the drum and brake pads, and heat between the
tires and the road. In the second mechanism "slamming on the brakes" and
locking the tires softens the rubber tires also reducing the friction.
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Update: June 2012