Anchoring effect

How mineral fibres work

Icon related to working mechanism of lapinus mineral fibres in brake systems. friction material

During braking, high shear forces are exerted on the surface of friction material. This results in wear debris. Mineral fibres show a strong anchoring effect in the upper layer of he friction material. They withstand the high temperatures in the sliding surface and are in direct contact with the disc, forming a Primary Plateau. In front of the fibres, the wear debris agglomerates and forms a Secondary Plateau. This is called the Anchoring Effect.

anchoring effect in friction material fibres brake pad

This illustration shows the primary plateau created by the mineral fibre, a secondary plateau and a third plateau created by wear debris.

A third body layer of wear debris

When braking, the generated waer debris is responsible for the formulation of a so-called third body layer. Depending on the initiation, growth and degradiation of this layer the actual friction coefficient and wear are generated. 

Mineral fibres play an essential role

To maintain the surface of the friction material effectively attached to the brake pad, anchoring points are needed. Mineral fibres can play a role here as they function as a primary plateau as shown above. During sliding friction, wear debris can agglomerate around the mineral fibres and start the formation of a secondary plateau. Anchoring points contribute considerably to improved friction stability and wear resistance. 

The presence of fibrous anchoring points is proven to be essential in obtaining optimal friction performance aspects, particularly when talking about copper free materials. In current copper-free formulations, the secondary pleateau cannot exist without these structural components in the friction material. 

Elements in a third body layer

The third body layer consists of a sei-continuous layer formed by primary and secondary plateaus and its composition depends on many factors. It is dependent on the components used in the friction material, the quality and composition of the disc, environmental conditions and the braking system in general. Plateaus are usually made up of iron oxide, copper, carbon, silicon and calcium elements. 

Positive effects of the Anchoring Effect on wear and vibrations

The Anchoring Effect has a positive influence on the friction level: more anchoring points means a bigger contact area, resulting in enhanced friction level. If managed properly in the formulation, the advantage of having many secondary plateaus results in a less abrasive formulation and a reduction of wear and vibrations. The best Anchoring effect is achieved by using short fibres that are optimally distributed in the friction matrix.