Brakes are everywhere in our lives, on passenger cars, trucks, trains, motorbikes, airplanes and other equipment like elevators, wind turbines, industrial equipment. They are fundamental to keeping people safe. They enable controlled stopping, prevent collisions, and make modern transportation and industry workable by managing speed and kinetic energy in routine and emergency situations. 

 

Braking is made possible by using friction materials. Friction materials come in many different shapes like brake pads, brake linings, friction paper, etc. These friction materials may face extreme conditions. During braking, the friction material comes into contact with a rotor, resulting in heat and friction. 

High aspect ratio mineral fibres play an important role in reinforcing the friction material. Our fibres have a direct effect on the tribology of the friction material by playing an active role in the formation of a third body layer. This layer helps enhance the durability and consistency of friction materials. 

 

Engineered to handle extreme heat and pressure, stone wool fibres help reducing wear, noise, vibration, and harshness (NVH). This results in stable friction behaviour, extended pad lifetime, and improved comfort and safety for users. 

 

Braking results from the surface interaction between the friction material and the brake rotor. The composition of the friction material plays a major role in overall braking performance. A typical friction formulation contains 10–25 different raw materials, each with its own chemistry, morphology and therefore a specific function. Finding the right balance between these functionalities is crucial in the development of friction formulations. 

The role of mineral fibres  

Mineral fibres are widely used in friction materials (both NAO and lowsteel) because they strengthen the brake pad surface, resist high temperatures and wear, and keep braking performance stable under all conditions.  

Friction automotive Lapinus brake pad system hands car passenger pcdp

Understanding tribology and the third body layer 

Tribology is the science and engineering that enables the understanding of friction, lubrication and wear phenomena between interacting surfaces.  

A third body layer is a thin, composite layer that forms between the brake pad and rotor during braking. This layer is essential for stable friction and efficient braking. Mineral fibres play an important role in the formation of a consistent third body layer. 

There are two mechanisms using mineral fibres which affect the formation of the third body layer and thus the friction performance: the anchoring, and reservoir effect.  

friction, stone fibres, manufacturing, functionality, lapinus

How mineral fibres enhance durability 

1. Anchoring effect 

During braking, high shear forces act on the surface of the friction material, generating wear debris. Short mineral fibres create a strong anchoring effect in the upper layer of the friction material.

They withstand the high temperatures at the sliding surface and remain in direct contact with the rotor, forming a primary plateau. In front of the fibres, wear debris accumulates and forms a secondary plateau. This phenomenon is known as the anchoring effect 

2. Reservoir effect 

Using longer mineral fibres will generate fibre nest during the mixing process. These nests generate a reservoir once they arrive at the surface of the friction material that retain wear debris. Using this effect helps to reduces wear, stabilizes friction, and reduces noise vibrations and harshness (NVH).  

3. Bonding 

Mineral fibres have a good bonding with the binder used in friction materials therefore contributing in improving the mechanical strength of the composite. By surface-treating mineral fibres with coupling agents, even improved bonding can be achieved. 

At ROCKWOOL Core Solutions, we offer premium quality mineral fibres and strong technical support for the friction industry. We go beyond being raw material supplier by researching the functionalities of our products together with other materials in the friction matrix. Rise to global challenges for friction, our team has continuously driven innovation for better solutions together with our customers. Rooted in sustainability, our highly bio soluble products contribute to shaping a better world for today and tomorrow. 

PROMAXON®-D Calcium Silicates

PROMAXON®-D features a unique spherical, porous morphology with a needled cavity structure. This allows manufacturers to control pad porosity precisely. It withstands temperatures up to 1500°C, complementing stone wool fibres to stabilise friction levels and enhance the NVH performance PROMAXON®-D is produced by Promat International N.V. and exclusively represented by ROCKWOOL Core Solutions in this industry. 

friction adc promaxon product

Heracron® Aramid Pulp

For high-performance brake pads, we offer Heracron® Aramid Pulp from Kolon Industries. These high-tenacity, fibrillated aramid fibres improve the mechanical bonding within the friction material, keeping fillers and short fibres tightly bound to avoid segregation. 

By reinforcing the brake pad structure, Heracron® Aramid Pulp enhances durability, stability, and give consistent friction under high temperatures and heavy braking. It also improves processing reliability, allowing manufacturers to achieve uniform pad density and performance across production batches. 

Millions of people every day rely on their brake pads, and millions of brake pads rely on our solutions. This product enables people around the world to brake safely.

Mike Palmen

Developing innovative mineral fibres solutions 

 

At ROCKWOOL Core Solutions, we work closely with friction material manufacturers to turn technical challenges into reliable solutions. 

Our team combines market insights, material science, and testing expertise to help customers develop friction materials that meet the needs of modern and future vehicles, including electric and hybrid powertrains. 

By contributing to international committees and industry forums, we ensure our partners benefit from the latest advancements and standards in brake technology. 

Our application development centre has a fully equipped pilot plant and test centre. It includes different mixing technologies, a full-scale passenger car noise dynamometer and Krauss testing equipment. These tools enable real-life simulation and performance validation, helping manufacturers shorten development time, optimise formulations, and achieve consistent, high-quality results. 

 

Interested in working with us? Contact us 

Access technical knowledge

 

Through our technical papers, our experts share technical knowledge, research findings, and testing insights. Topics range from friction material formulations to NVH performance optimisation, helping manufacturers improve product quality and adapt to evolving industry standards. 

 

Disc brake of the vehicle for repair, in process of new tire replacement. Car brake repairing in garage.Suspension of car for maintenance brakes and shock absorber systems.Close up. BRAKE PAD, lapinus
Mike Palmen Friction automotive Lapinus

Mike Palmen

Key Account Manager Automotive,
ROCKWOOL Core Solutions

Mark Segeren Lapinus

Mark Segeren

Business Manager Automotive & OEM,
ROCKWOOL Core Solutions