Brake Pad Compressibility
The compressibility of brake pads consists of measuring the thickness change in μm under a defined uniaxial pressure or how much a brake pad can be pressed together. Pad compressibility can be an important design parameter of braking systems, which significantly impacts brake performance, comfort, and behavior that the driver experiences, as well as noise and vibration development. Among ingredients like phenolic resin, metallic and non-metallic fibers, fillers, abrasives or lubricants, which can be contained in brake pads, only a few are well known to directly affect compressibility, like graphite, rubber or so-called “Friction Dust”. To address this challenge, Superior Graphite has developed Resilient Graphitic Carbons (RGC™) that help control brake pad compressibility.
How can we help address your challenges?
Formulators have difficulties adjusting the compressibility of pads, which can negatively impact brake comfort as well as pedal feel and can cause unwanted vibrations.
RGC™ is a proven solution to increase cold and hot compressibility even with a limited addition of 2-3% in weight. RGC™’s increased porosity and resiliency assists in adjusting pad compressibility. In addition, the open surface porosity of RGC™ promotes a strong bond with the phenolic matrix, which results in the reduction of fading phenomena, especially at high temperature.
Some formulations experience excessive noise during the braking function.
Very often, noise is a result of vibrations occurring at different frequencies. An RGC™ addition at a range of 2-5% in weight, or in replacement of other graphite or CPC, reduces vibration and thus noise. This is attributed to its damping capacity, which is related to its unique morphology and porosity.