Welllllll, I’m getting way to technical. Don’t think of it as a chemical stopping power. On the micro scale, NOTHING is touching anything; it’s all electron atom repulsion. Friction is technically a force trying to take electrons from another atom. Glue is a chemical bond, extreme friction. Velcro is a low friction bond but works by wanting to stick together, this is how the brake pad material works when bedded in. It’s still a friction thing but more on the chemical level as an electron transferring proses vs a chemical bond. In more technical simplicity,
Your brake pads against raw steel rotors are an Ionic repelling frictional proses vs pad material to pad material is a Covalent bond proses.
I have no idea about ceramic carbon fiber new age brake systems, I would assume it’s still a repelling ionic resistance friction but there is no brake fade.
The key is the brake fade, at low speeds, you don’t even need the rotors to be bedded in, cold brakes work as typical friction only, and it’s when they got hot that the friction increases due to this Covalent bond stuff, thus increasing friction.
Sorry if I got too much science’y all up in here.
some sources if you dont get what im saying or dont habeeb it
http://www.chemistryislife.com/t-4
https://www.bendix.com.au/sites/default/files/news-uploads/0708_bendix_general_ct_-_braking_performance_without_the_bra.pdf
I am not very good at describing what i remeber. read this link above. every simple.
"The brakes convert kinetic energy of a moving vehicle into heat. The simplest way for a
brake system to absorb kinetic energy is to break chemical bonds in the rubbing surfaces of
the brake pads and rotor. This is called "abrasive friction", because the pads and rotor act as
an abrasive, pulling each other apart, wearing, and turning the pad into dust.
A more sophisticated way to absorb kinetic energy is "cohesive friction" (or adhesive
friction). Cohesive friction is used in modern non-asbestos organic (NAO) friction materials
such as Bendix General CT.
In order to use cohesive friction, pads deposit a film of friction material on the surface of the
rotor. As the rotor passes between the pads, the film and the pad surface heat up and
become sticky. The pads and friction film bond to each other then break apart, absorbing
energy. They bond and break apart continuously as the rotor passes between the pads.
Cohesive friction relies on the surface properties of the friction material and transfer film,
which change with temperature. A material that is sticky at 30°C might be very slippery at
150°C. This means that an adhesive friction material must use a cocktail of adhesive
ingredients to maintain the "sticky" properties over a range of temperatures.
Used under its design conditions, a cohesive friction material does not wear the rotor at all,
as the rotor iron is protected by the friction film. The pads wear slowly, just enough to keep a
supply of adhesive materials at the surface.
No material loss from the pads and rotors means no brake dust.
Cohesive friction is not possible at extreme temperatures, as the adhesives lose their
effectiveness when they get too hot. The only friction available at high temperatures is
abrasive, resulting in accelerated wear for pads that are not optimised for these conditions.
In frequent or sustained high temperatures, a purpose-designed high-performance friction
material should be used. In order to meet their high temperature operating requirements,
high performance materials must use abrasive friction. More abrasion means more dust. "
