Disc Brakes.
The best place to start is by defining what it is that you want to study.
The whole subject of using friction to retard a vehicle is quite lengthy.
So define what you mean by braking temperatures and the circumstance.
Essentially a disc brake works by turning the energy of the vehicle into other forms of energy. The amount of work done and the resultant energy transformation can be calculated by the mass of the vehicle and the deceleration required. A secondary consideration is the frequency of the decelarative action.
The amount of work done will dictate the materials required. You need to examn the ability of the material to absorb and radiate heat and its ability to act as a heat sink.
You might examine and contrast these abilities of , say, Steel and grey Cast Iron, Carbon matrix and Sintered Ceramics (SCs are what is now used as aircraft brake rotors. If you think stopping a 700kg F1 car from 200 mph in 100 metres is tough, consider stopping a 700,000 kg 747 from 200 mph in 3500 metres London Heathrow).
Brake Fluids.
Most Brake fluids will be Dot 3 or 4 polyglycols or Dot 5 silicon brake fluid.
Boiling temperatures Dry are:
DOT 3 401° F
DOT 4 446° F
DOT 5 500° F
and wet are:
DOT 3 284° F
DOT 4 311° F
DOT 5 356° F
Since polyglycols are hygroscopic, there are design criteria to keep in mind when designing a brake.
However silicon fluids are slightly compressible especially when they get hot. (Which may explain why some karters using DOT 5 can never 'bleed' their brakes, it's the hot fluid compressing, not air in the system at all)
Lastly one has to match the pad material and design to the application. One obviously has to match the available pressure (amount available from an adult driver will differ from that of a cadet, let alone vacuum assisted or powered brakes) with the degree of friction and teh wearability of the brake.
Brakes will deposit some of their material on the rotor surface. When this comes again into contact with the pad as a 'rough lump' it will get hot (very hot). Sometimes that heat will affect the rotor material, converting grey cast iron or steel into different material (cementite)
Also research abrasive and adherent friction.
(incidentally, breaking the glaze on a rotor with emery paper is regarded as a bad thing, the process embeds the emery in the disc, promoting the next layer of glaze)
You can get a lot of material from the internet.
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Expert advice needed on braking facts and figures by 'dan01' (03 Nov 2008 @ 13:12)
