Carbon Fiber and Car Parts: Interesting Things About Brakes
There has been a lot of talk in recent months about encouraging the auto industry to use more carbon fiber in new cars. As the thinking goes, carbon fiber has a greater strength-to-weight ratio that could end up being key to making electric cars the norm. Still, carbon fiber and other composites cost too much to manufacture right now. Carmakers need costs to come down before they will go any further. In the meantime, the racing industry continues to show just how awesome carbon fiber is.
For example, were you aware that carbon fiber brakes are all the rage in pro drag racing these days? As cars get faster and faster, they need more muscle to slow them down at the end of the race. Parachutes are a good starting point, but what happens when chutes fail? Car owners and drivers alike want something that can still stop a speeding drag racer before it becomes a heap of scrap metal.
Dragzine’s Mark Gearhart explained some of the reasons carbon fiber brakes are catching on in a February 23 (2018) piece published on the magazine’s website. According to Utah-based composites dealer Rock West Composites, much of what is described in the article is directly related to some of the unique properties exhibited by carbon fiber. Let’s look at them.
Reaction to Heat
Carbon fiber brake discs and pads react differently to heat compared to steel. In fact, carbon fiber’s reaction is that which makes the material so intriguing for car brakes. Where steel brakes initially bite well before beginning to fade with heat buildup, carbon fiber brakes do just the opposite. This is why, according to Gearhart, some drivers using carbon fiber brakes for the first time are very uncomfortable.
In excess of 200 mph, carbon fiber brakes can feel unresponsive when first deployed. It takes a second or two for the heat to build up. What it does though, carbon fiber bites a lot more aggressively than steel. The more heat, the better the carbon fiber brakes work. Steel brakes are just the opposite.
Resistance to Heat Damage
Drag racing teams relying on steel brakes rarely get through a season without changing the rotors at least once or twice. Teams that rely on carbon fiber can, under most circumstances, get through an entire season on the same rotors. That’s because carbon fiber resists heat extremely well.
Even though carbon fiber brake pads and discs bite better when they are hot, they do not warp or otherwise distort when subjected to high heat. They are also less likely to break apart because of their high strength-to-weight ratio. That makes them a better option in a sport that combines extremely high speeds with high heat.
Impractical for Street Use
The way carbon fiber reacts to heat makes brake pads and discs constructed using the composite material impractical for street use. Carbon fiber brakes are great for drag racers because of the tremendous heat braking generates, but passenger cars and even heavy-duty trucks do not require the same braking power generating the same amount of heat.
It could be that carmakers will find a way to incorporate parts of the carbon fiber braking system in future passenger cars. That would not be so surprising, given how involved the auto industry is in building race cars. But for now, carbon fiber brake systems will be reserved for the drag strip and the race track. Those drivers who trust their lives to reliable equipment will know their carbon fiber brakes will slow them down even amidst parachute failure.