ceramic%20 disc%20brakes
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nitrous oxide used in auto trends...TRANSCRIPT
ANEESH K.KS8 PRODUCTION
ROLL NO: 503
CONTENTSBraking systemTypes of braking systemDisc brakes Ceramic disc brakesCeramic disc brakes and conventional disc brakesManufacturing of ceramic disc brakesPCCBAdvantages & Disadvantages of ceramic brake
discApplications
MAIN REQUIREMENTS
Brakes must be strong enough to stop the vehicle within the possible distance in an emergency. (safety)
Brakes should have good anti-fade characteristics also on constant prolonged application its effectiveness should not decrease.
STOPPING DISTANCE OF A VEHICAL DEPENDS Vehicle speedCondition of road surface.Condition of tyre thread.Coefficient of friction b/w tyre thread & road
surface.Coefficient of friction b/w brake disc/drum &
brake pad.Braking force applied by the driver.
TYPES OF BRAKESAccording to the purpose
Service or primary brakes Parking or secondary brakes
According to the construction Drum brakes Disc brakes
According to the method of actuation Mechanical brakes Hydraulic brakes and Air brakes Electric brakes Vacuum brakes
According to the extra braking effort Servo brakes or power assisted brakes Power operated brake
DISC BRAKE
TYPES OF BRAKE MATERIALSGrey cast iron disc
Heavy Rust formation
Aluminium disc Light Less resistant to heat and fade
Carbon-fiber disc Heat resistant Needs high working temperature
Ceramic disc Inorganic and non-metallic Hard and brittle material High heat and abrasive resistance Can sustain large compressive load
CERAMIC DISC BRAKES AND CONVENTIONAL DISC BRAKES
Grey cast iron disc is heavy which reduces acceleration, uses more fuel.
Ceramic disc brake weighs less than conventional disc brakes but have same frictional values, used in F-1 racing cars etc.
CDB good at wet conditions but conventional disc fails in wet conditions.
CDBs are 61% lighter, reduces 20kg of car, apart we can save the fuel, resulting in better mileage. Improve the shock absorber. We can add more safety features instead of the current weight.
MANUFACTURE OF CERAMIC DISC BRAKEIn earlier days disc brakes were made from
conventional brittle ceramic material. DIAMLER CHRYSLER made carbon fibre
reinforce brake disc to avoid the brittle property.
Short carbon fibres + carbon powder + resin mix(at 1000 ْ c sintering) = stable carbon frame work.
After cooling ground like wood brake disc obtains its shape.
Add silicon to the required shape and insert in the furnace for the second time.
Resins : thermo plastics resins and thermo setting resins .
COATING OF CERAMIC ON CONVENTIONAL BRAKE DISCS
FRENO Ltd. used metal matrix composite for disc, an alloy of aluminum for lightness and silicon carbides for strength. The ceramic additive made the disc highly abrasive and gave a low unstable coefficient of friction.
SULZER METCO Ltd. special ceramic coating, developed thermal spray technology as well as manufacturing plasma surface.
PORSCHE CERAMIC COMPOSITE DISC BRAKES (PCCB)
This is manufactured using a high vacuum process.
The process involves heating carbon powder, resins and carbon fibres in a furnace at 1700 ْ c
PROPERTIES OF PCCBCDB with the involute cooling ducts for an
efficient cooling. Offers braking response, fading stability,
weight & service life. PCCB ensures maximum deceleration from
without any particular pressure on the brake pedal.
Superior response under wet condition. New braking linings cannot absorb water. Cross drilled brake discs help to optimize response of
the brakes also in wet weather.
ADVANTAGES50% lighter than metal disc brakes, reduces 20kg
of car. Apart from saving fuel also reduce unsprung
masses with a further improvement of shock absorber response & behavior.
High frictional values in deceleration process Porsche- 100 to 0 km in 3 sec.
Brake temperature. Resistance up to 2000 ْ c .Still runs after 300000 km need not change CDB.No wear, maintenance free and heat and rust
resistant even under high oxygen concentration.Heavy commercial can be braked safely over long
distance without maintenance.
DISADVANTAGE
High initial cost and high cost of production.
APPLICATIONSFORMULA-1 cars and sports carsPorsche 911 turbo- with a top speed of 305
km/h and acceleration from rest to 100 km/h in 4.2s. Its engine 3.6 L with 420 hp max torque 560 Nm is still running with PCCB.
911GT2 and Mercedes Benz’s futuristic vision GST is going to reinforce CDB .
APPLICATION IN PORSCHE 911
CDB IN UPPER CLASS LIMOUSINES
CDB IN SPORTS CARS
CONCLUSIONCDB due to its advantages over the
conventional brake discs are going to be the brake disc for cars in the future. With the success of Porsche turbo car, many other racing cars and commercial vehicles are going to implement CDB in cars.
REFERENCES
AUTOMOTIVE MECHANICS – CROUSE/ANGLIN
www.porsche.comwww.diamlerchrysler.comwww.mercedesbenz.comwww.howstuffworks.com
QUESTIONS