What are the types of brake pads available on the market?

When we are about to close the purchase of our future vehicle, whether new or used, I think we can count on the fingers of our hands the number of people who check which braking system their car is fitted with. It may seem a trivial matter, but if we are not aware of what makes our vehicle stop, we may get a nasty surprise on a couple of occasions: during an emergency stop or when we have to take it to the workshop to replace some part of the braking system.

Disc brakes and drum brakes

First of all, we need to be clear about the two braking systems a vehicle can have. Starting with the most rudimentary, we find drum brakes, which are increasingly obsolete, since it is now hard to find them on new vehicles except in the lowest ranges. These brakes began to lose prominence as the power of vehicles increased, making the need for even more effective braking imperative.

Drum brakes did their job until they were no longer so necessary, not only because of their braking capacity compared with disc brakes, but also because of other qualities that placed them below the former: poor capacity to dissipate the heat generated during braking and, in addition, poor capacity to remove water or moisture from inside them, which could lead to scares when their ability to brake properly was diminished.

In response to these, disc brakes were born, far more effective and of various types depending on the characteristics of our vehicle. The simplest are solid discs, which we normally find on smaller and lighter vehicles; on an intermediate step, and as the most widely used option, are ventilated brake discs, which are simply two discs joined together with cut-outs in their body to improve cooling; while on a higher step we find an evolution of the above with another type of cut-outs, which also serve to channel air, and which are fitted to high-performance vehicles. At the top of them all are the carbon-ceramic brakes, intended for large sports cars because of their components, lightness and braking capacity.

Types of brake pads

As you know, disc brakes use pads that stop our vehicle and which can be made from different compounds. These pads are mounted in another component of the braking system called the calipers, which press the pads against the disc by means of their pistons when we press the brake pedal to stop the vehicle. Over the kilometres, these pads gradually lose thickness, so sooner or later the time will come to take our car to the workshop to replace them.

Normally, the workshop you visit will fit the pads specified by the manufacturer again, but if you prefer to choose them yourself or want to know what is being fitted, you should know that you can find several types of brake pads on the market, whose characteristics will vary depending on the type of vehicle and our driving style:

• Semi-metallic brake pads: These pads are characterised by containing around 30% to 65% steel wool, copper or iron powder mixed with inorganic fillers. With these pads you will gain in durability and they transfer heat efficiently, being especially effective in aggressive driving or demanding situations, especially the hotter they get, but they will be less efficient in cold conditions.
• Organic brake pads: These brake pads are manufactured by mixing components such as glass fibres, rubber, Kevlar and carbon. Thanks to these pads you will have effective braking in practically any situation, and they are the quietest, but they wear out faster, creating more dust on the wheels and, in addition, they can overheat and melt under very aggressive or extreme driving.
• NAO brake pads: These are very similar to the previous ones, but differ in the incorporation of a small amount of metal, between 10% and 30%, which improves braking and heat dissipation. Logically, having this additional amount of metal, they will be noisier and will also generate more dust on the wheels.
• Ceramic brake pads: Ceramic brake pads are manufactured using ceramic fibres, bonding agents, non-ferrous materials and very small amounts of metal. You will recognise these pads from high-performance vehicles; their use in them is no coincidence, since they allow very effective braking, superior to the previous types, and are also quieter and cleaner, but on the other hand, as you can imagine, they are the most expensive for our pocket.