Abrasive Friction Vs Adherent Friction Part 2

Part 2

There are two types of friction involved when you put your foot on the brake pedal, abrasive friction and adherent friction. In part two we will cover what adherent friction is and if it is better or worse than abrasive friction.

What Is Adherent Friction?

Adherent friction is a friction mechanism where a thin layer of brake pad material bonds to the surface of the rotor. This transfer layer of brake pad material, once evenly established on the rotor, is what comes into contact with the brake pad surface during the braking process.

The benefits of adherent friction

Once the brake pad material is sufficiently transferred to the surface of the rotor, it creates what we call sticky brakes. The material transferred acts as a sort of adhesive that literally sticks to the brake pad as it’s being compressed against the rotor. What this does is create a barrier between the pads and the rotors so that the rotor is not being ground down to a powder by the brake pads.  What this benefit really means is that your brakes will last significantly longer. Since the rotor is not being ground down the rotors almost don’t wear, which means they will last a very long time without being damaged. There is no brake dust. Again, because there is no wear, there is no brake dust. Your pads will last 10-20 times longer. Adherent friction is not nearly as a destructive of a force so the brake pads are not being worn down as fast. Increased stopping distance. Because there are two forces at work here, adherent friction and pressure, the brakes stop the vehicle up to 20 percent shorter. This is a really important point. We all want brakes that will last a long time, but at the end of the day we want brakes that will save our lives. Having the confidence that your vehicle can stop on a dime every single time is something worth investing in.

How To “Seat” The Brakes

One thing that is often misunderstood about adherent friction brakes is that you have to go through a “seating” process before you start to notice a difference. When you first put the brakes on there is no material transferred from the pads to the rotors yet, so when you first drive on them they won’t feel any different. It will take 50-100 miles of braking to really get a transfer film built up onto the rotors. Once that film is fully applied, you will notice a huge difference in your brakes. So give it time and you will notice a difference. You will even be able to see the film on the rotors, it will look like an even black strip around the rotor. It might not look very good but that is exactly what is supposed to happen, it’s the secret to the brakes having such great stopping power. Once you see the strip on the rotors you know your brakes have been properly seated.


Adherent friction brakes are worth every penny. They stop shorter, last longer, and are not harmful to the environment. It really is a no brainer. Can you imagine never having to replace your brakes or rotors again? Then give PureForge® rotors a try, you won’t regret it.

Allan Sicat