While regulations surrounding emission standards often focus on tailpipe emissions, brakes and tires actually contribute 32 percent of driving-related particulate emissions. Half of that comes from brake dust alone. On Wednesday, Bosch revealed its answer to a cleaner brake disc called the iDisc.
Bosch says the iDisc offers numerous benefits over traditional cast-iron brake discs. Foremost, the iDisc's construction consists of a tungsten-carbide coating after the disc's friction rings are mechanically, thermally, and galvanically treated. The special process creates a more durable disc and one that produces 90 percent less brake dust for cleaner air. Bosch said the iDisc is roughly three times more expensive than a standard cast iron disc, but it's also three times less expensive than a ceramic brake disc.
And the iDisc doesn't sacrifice performance when compared to a ceramic brake disc. Bosch claims the brake fade performance of its iDisc mimics ceramic brakes and little deceleration wear occurs over time. Depending on the carbide coating's strength, the company said the iDisc will last twice as long as a conventional disc. The iDisc is also resistant to corrosion, which offers a major advantage for electric cars and regenerative braking systems.
Bosch didn't provide specifics but said it will begin production of the iDisc for an unnamed automotive manufacturer this month. We happen to know that manufacturer is Porsche and the brakes will be offered on the 2019 Cayenne. Porsche calls them Porsche Surface Coated Brakes (PSCB) and says the tungsten-carbide mixture is essentially burned onto the surface using a high-velocity oxygen fuel, creating a hardened surface that is 100 microns thick. While thin, this is the usable surface of the rotors, and Porsche says it is good for 30 percent to twice as much wear, depending on driving style. Porsche charges $3,490 for its PSCB brakes compared to $9,080 for its carbon ceramics on the Cayenne.
While price may be an issue for the technology at first, the company expects economies of scale will help make the iDisc a go-to option for future cars.