Brass Fiber

Brass Fiber is a multifunctional metallic reinforcement designed to dramatically improve the properties of the friction composite. Its key functions are:

• Three-Dimensional Mechanical Reinforcement: Unlike chips, fibers create an interconnected 3D metallic network within the resin matrix. This provides superior crack resistance and structural integrity by "stitching" the material together at a microscopic level.
• Excellent Thermal Conductivity: Like chips, brass fiber is a very effective thermal conductor, dissipating heat from the interface to prevent fading and reduce wear from thermal degradation.
• Friction Stabilization: It contributes to the formation of stable plateaus and improves the pad's hot compression resistance.

The main difference is morphology and the reinforcement mechanism:

• Chip: Acts as a discrete reinforcing filler and a thermal conductor. The reinforcement is more localized.
• Fiber: Possesses a high aspect ratio (length/diameter). It acts as a continuous reinforcement that creates a metallic skeleton within the pad. This translates into significantly greater toughness and resistance to crack propagation.
• Application: The choice depends on the goal. For maximum mechanical reinforcement, fiber is superior. For an optimized balance between thermal conductivity, processability, and cost, chips are an excellent option. They are often used in combination.

This is a core competency of RIMSA. Turning recycled brass fiber into a high-specification raw material is a controlled process:

• Rigorous Source Selection: A thorough control of material sources is carried out to ensure a base with the proper chemical composition and cleanliness.
• Advanced Production Process: RIMSA applies cleaning, drying, sorting, and dimensional control processes to ensure that each batch meets the specifications for length, diameter, and purity.
• Guaranteed Consistency: The result is a fiber with consistent geometric and chemical properties, which ensures predictable behavior in the mix and in the final performance of the brake pad.

The considerations are the same as for metallic chips:

• Copper Content: The copper from the brass alloy counts towards the "Copper-Free" regulations (SAE J2975), so the dosage must be carefully controlled by the formulator.
• Lead (Pb) Content: Recycled brass may contain traces of lead. RIMSA, thanks to its strict quality control, manages and minimizes the presence of this element, offering a product that complies with the most demanding regulations.

Geometry is a critical parameter that the formulator must consider:

• Fiber Length: Longer fibers provide greater macroscopic reinforcement but can be more difficult to disperse homogeneously and may affect the preform's density.
• Fiber Diameter: Finer fibers offer a larger specific surface area for adhesion with the resin but can increase its demand in the mix.
  The choice of geometry is a trade-off between the desired mechanical properties, processability in the mix, and material compaction.