Vitrification of the friction surface
Cause: Inadequate contact pattern, no cleaning braking after temperature load
Contamination of the friction surface
Cause: The operating temperature is often not reached; self-cleaning does not take place. Contamination of the friction surface by, e.g., corrosion, dirt, paint, or salt.
Deep scoring in the pad surface
Cause: Use of scored brake disc. Ingress of foreign bodies such as dirt, salt or corrosion. Inadequate distribution of friction particles in the friction material.
Residues – metal pick-ups in the pad surfaces
Cause: Material transition from the brake disc onto the brake pad due to, e.g., different loading, climate and/or material incompatibility.