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CERAMIC DISC BRAKES
CONTENTS
Braking system
Types of braking system
Disc brakes
Ceramic disc brakes
Ceramic disc brakes and conventional disc brakes
Manufacturing of ceramic disc brakes
PCCB
Advantages & Disadvantages of ceramic brake disc
Applications

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 speed
Condition 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 BRAKES
According 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
TYPES OF BRAKE MATERIALS
Grey 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 BRAKE
In 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.

PROPERTIES OF PCCB

CDB 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.
ADVANTAGES
50% 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.


APPLICATIONS
FORMULA-1 cars and sports cars
Porsche 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 Benzâ„¢s futuristic vision GST is going to reinforce CDB .

CONCLUSION
CDB 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.