We’ve often seen sports cars and modified cars with big, cross-drilled brake discs. Some systems are even a step further – they’re carbon-ceramic.
But, how exactly do cross-drilled and slotted brake discs improve braking performance?
Unfortunately, the heat generated during this process causes two highly undesirable situations. First, due mainly to heat conduction, the brake fluid in the calliper experiences temperatures that could lead to boiling.
Second, and of greater concern, is the drastic reduction in friction. This is the condition called brake fade and is most commonly known to occur when braking during a long downhill gradient.
CROSS-DRILLED BRAKES RESIST OVERHEATING
Overheating can also occur during repeated hard braking whether downhill, uphill or on flat ground. So, brake cooling is an important consideration in design. The heat generated needs to be dissipated into the atmosphere as quickly as possible. Forced cooling (with a fan) is not practically feasible.
So, an alternative is natural cooling aided by ducts. This, however, requires various other aerodynamic issues to be addressed, so that a constant flow or air is maintained. Ventilated discs are another solution to fast cooling.
Cross-drilled brakes are highly effective in accelerating the cooling process even further by shortening the heat transfer path to the atmosphere.