Never said it was the same thing as welding, but the same principle, yes. What I meant is that the two metals (brake pads and discs) get hot enough to where one of them will break down to the point where it can leave traces of itself on something. Hopefully the pads do this first and leave their mark on the disc.
I'm not trying to argue with anyone, especially now that people are actually treating me with some form of respect. I just find it really hard for me to believe that a race car can slam on it's brakes at 200mph, all the way down to 35mph and their rotors won't "warp" yet us Jeepers can have "warped" discs from 35mph to 5mph in in instant.
Also, some of you seem to be attacking my "rotors do not warp" statement in full barrage. I never thought of the water scenario, so I was proved wrong in that aspect. I don't, however, know how true-to-aim the lug nut scenario is. I've almost had my wheel come off due to impact gun torquing, and while my wheel whobbled on the studs, my braking was still fine. No variation what-so-ever. That's my own personal experience.
Rawbrown: Change your brakes, and do not beed them. Tell me if tightening your lugs nuts keeps away "warpage." :sunshine: Brake fade is not caused by the gases on the brake pads. It is caused when the boiling point of the brake fluid is exceeded and boils. It forms air pockets and when you apply pressure to the brakes, the air compresses creating a sponge feeling in the pedal. Actually... you are half right on the lug nut scenario. This is how I see it though. If you tighten all of them to spec, all but 2, then the rotor will be somewhat lopsided to the caliper/pads. Regardless of full pad contact, the pad will still hit the disc evenly (as per pad to disc contact, not full pad contact) and take away some of the pad and disc metals. Doing so for prolonged periods of time with wheels not properly torqued, will mold the disc in a slanted fashion. It will be slanted because of not being torqued correctly and eventually forming to the pads contact because of the torque specs. When you do decide to actually torque everything down the way it should be, the pads will NOT move, but the disc WILL move. This will create vibration in the pedal... and that is when a lathe is needed. I would not call that warping, which most people see as the disc getting too hot and not being able to disappate the heat quick enough. It has nothing to do with the types of pads, or discs you use... if you slant the disc it will happen to any disc, regardless of cross-drilling or slotted, or both.