There is a lot of press from ceramic brake pad manufacturers and distributors claiming ceramic materials are superior in comparison to semi-metallic formulations.
Semi-metallic versus Ceramic
It is true that nearly 30% of new auto manufacturers are equipping their vehicles with ceramic brake pads now, but this should not warrant a brake pad swap in every situation. There are some benefits to using ceramic pads, but drawbacks exist in every situation.
To understand the differences between the two types of brake pads, you must understand how they are constructed. Ceramic brake pads are generally composed of dense ceramic material and embedded copper fibers. Semi-metallic brake pads, on the other hand, are made from synthetic resins and embedded metal fibers (generally steel).
BRAKE DUST COMPARISON
Ceramic brake pad sellers usually boast their ceramic pads produce less brake dust than a semi-metallic pad. It is true that ceramics do produce less dust per given time unit, and the dust is harder to see because of its lighter color. Ceramic brake dust is also less sticky, and less of it actually ends up on the vehicles’ tires.
BRAKE PAD DURABILITY AND COST COMPARISON
Less brake dust generated per unit time from ceramic pads is a result of the pad material being more durable than its semi-metallic counterpart. A ceramic pad therefore requires less frequent brake pad changes than a semi-metallic pad. Since ceramic brake pads cost less overall in terms of total pads purchased, the choice seems obvious to a novice brake purchaser.
What gives this calculation a false reality however is the fact that ceramic brake pads cause more abrasion to brake rotors than a semi-metallic. Brake rotors happen to wear faster when using ceramic brake pads because the pad itself is bearing less of the brake load.
Because braking force transcends through friction, some material will need to be transferred from one part of the braking mechanism to the other, one way or another. Brake rotors are more expensive than brake pads, and replacing them ends up costing more in the long run to the consumer. This is the reason it is more economical to use semi-metallic brake pads.
BRAKE NOISE COMPARISON
You will also hear from ceramic brake pad sellers that by adding ceramic brakes to your vehicle, braking noise will be reduced. This statement is also true, and is possible because the pad material vibrates at frequencies outside of what the normal human ear can hear as opposed to semi-metallic.
Ceramic brake pads do not hold as much heat as a semi-metallic brake pad, and therefore are considered to be the best choice for high performance braking. This element is true about ceramic brakes as well, but because the ceramic material does not hold heat effectively, the rotor ends up taking on this heat as a byproduct. Race vehicles use these ceramic brake pads to prevent brake glazing and/or overheating during prolonged periods of braking. Additionally, these race vehicles are using both oversized brake kits and rotors to help compensate for the fact the pads will be absorbing less of the heat generated by the braking activity.
For the highest performance braking on the street, you should be using a semi-metallic brake pad because it will give your vehicle the greatest amount of friction and ability to transfer kinetic energy to heat. When on the street, the semi-metallic pad will operate very well in short bursts given adequate amounts of time between braking sessions to cool off.