b'Searching for the rightanchors. That, of course, means wear and tear, composite saysLeber.Italsomeansbrakedust,but90 percent less than what youd get with a gray-iron The pads required at least as much developmentbrake. Moreover, the tungsten carbide discs have effort,saysLeber.Lasertechnologyandaservicelife30percentlongerthantheir high-precision, automated production processesgray-ironcounterparts.Thisputstheirperfor-for a new type of disc are one thing. Pads with themance levels close to those of the PCCB, but at right composite are another. A surface as smoothonly one-third of the cost of the ceramic brakes. as a mirror needs a special pad thats adhesive.And the new brakes feel like the PCCB in practice.Matthias Leber: head of the brake division and the Imagine running your inger with light pressureThe pedal force remains constant, even when themastermind behind the PSCB.overamirror;itdoesntslideuniformlybutbrakesarehot.Thesebrakesdontshowthe instead keeps sticking for an instant. However, andreaded fading behavior at high temperatures. On overly soft pad on a very hard surface would wearthecontrary,theyworkallthemorecrisplyatClean as a whistledown too quickly at high disc speeds. So the engi- temperatures above 600 degrees Celsius.neers added some very hard materials to the pad: microscopic particles that penetrate the tungstenAfter around six thousand kilometers of normal carbide coating. These pads positively cling to theuse, the brake pads have polished the surface of disc. the disc to a shine. Their color then matches the whiteten-pistonixedcalipersinthefrontand the four-piston ixed calipers in the rear, whose technologyisfamiliarfromthePCCB.Butwhy white? Leber laughs. If a brake produces practi-cally no dust, you want to advertise that fact. My color proposal met with a lot of initial resistance. But after thousands of kilometers, the brakes on thenewPorscheCayennetestvehiclesarestill clean as a whistle.IsthePSCBtheperfectcombinationofperfor-mance,aesthetics,andcosteffectivenessand thus the holy grail of brake development? Leber shakeshishead.Aselectriicationmakesever greater advances in automotive engineering, itll also bring new types of brakes. Recuperation, for Microscopic anchors example, is a completely non-wear type of decel-1) Thermally treated surface: lasers structure, abrade,eration, which makes it all the more interesting, and clean the gray-iron core. because at some point well be able to use it for 90 Theresultsurprisedusall,saysLeber.We2) Ductile interlayer: nickel applied in a galvanicpercent of all standard braking action. We have to already knew that the brake would be good, butprocess helps bind the gray iron and tungstenkeep working on it. After all, fast cars need fast theirsttestsexceededallourexpectations.carbide. brakes.SoPorschebrakescanneverbefast Thanks to the smooth surface, the full pad imme- 3) Hard-metal coating: this consists of tungstenenough.diately starts covering the disc at low speeds. Youcarbide, flame-sprayed on at high velocity. By Thorsten Elbrigmanncould compare it to the difference between a vinylPhotos by Frank RateringrecordandaCD:unlikegrayiron,tungsten4) Brake disc and caliper: coated lightweight carbide has hardly any grooves and is smooth as agray-iron brake disc with a ten-piston fixed caliper.mirror, so there are no hollows to reduce the total5) PSCB brake pads: they have a newly developed amount of surface area. When greater stoppingspecial material.power is needed at high speeds, the hard compo-nents of the pad throw out their microscopic32'