To get acquainted with passenger car brake pads, it must first be understood that brake pads are part of the disc brake system used in cars and some other industries. Brake pads consist of steel plates at the back and friction materials attached to the metal surface, which face the rotating brake disc.

Brake pads are one of the important and sensitive components in every vehicle and are today considered super safety parts with an A-grade standard due to their critical role. This is because their quality and performance directly impact the safety and health of vehicle occupants.

Role and Function of Brake Pads
Brake pads generate appropriate friction force to convert the kinetic energy of a rotating wheel, powered by the engine, into thermal energy. This thermal energy is then dissipated into the environment, resulting in the vehicle slowing down or stopping.

Brake pads must have a high and stable coefficient of friction, retain their properties despite temperature changes, resist wear, and not scratch the brake drum.

How the Brake System Works
When you press the brake pedal, a cylinder activates, pushing brake fluid through hoses down to the calipers. The calipers engage the brake pads, which press against the rotor connected directly to the wheels. This pressure creates the necessary friction to reduce the vehicle’s speed or stop it. As the rotor slows down, the wheels slow as well.

When you release the pedal, the process reverses: the pads disengage, fluid returns through the hoses, and the wheels begin moving again.

Brake Pad Characteristics
Key characteristics considered when selecting materials for brake pads include:

• Resistance to brake fade due to temperature rise from converting kinetic energy into heat.
• Resistance to moisture effects on braking performance; brake systems should be designed to resist water, at least temporarily.
• Ability to quickly recover from temperature or moisture changes and maintain nearly consistent friction throughout drying or cooling.
• Appropriate coefficient of friction that is low enough to prevent wheel lockup but high enough to provide sufficient stopping force. Typically, friction coefficients range from 0.25 to 0.6.
• Resistance to corrosion caused by friction without accelerating wear of brake discs.
• Uniform and balanced contact with the brake disc or drum surface; some materials may fragment over time causing pits, grooves, or damage.
• Ability to provide suitable friction force with quiet operation.
• Proper compressibility; overly compressible materials increase stopping distance. Brake pad materials should be porous and permeable to prevent water from affecting friction.

Materials Used in Brake Pads
Environmental considerations affect material choice. After World War I, asbestos was commonly used due to its heat resistance and friction properties. However, due to health hazards, asbestos was gradually replaced.

Today, brake pad materials fall into four main categories:

• Non-metallic materials: Synthetic composites made mainly of cellulose, aramid, polyacrylonitrile, and glass fibers. They cause minimal disc wear but generate much dust and have shorter life spans.
• Semi-metallic materials: Composites mixed with varying amounts of metal particles. They are harder, more fade-resistant, and more durable than non-metallic pads but cause more disc wear and require more force for braking torque.
• Fully metallic materials: Used mostly in racing vehicles, made from porous steel without synthetic additives. They have very long life but cause rapid disc wear and produce significant noise.
• Ceramic materials: Made from clay and ceramics combined with copper fibers, balancing durability and fade resistance with quieter operation. However, ceramics dissipate heat less effectively, possibly causing warping. They are exceptionally quiet.

Additionally, phenol-formaldehyde resin is commonly used as a binder. Graphite may serve as both binder and friction material. Zirconium silicate is also used as a friction compound.

Typical brake pad components include: white clay (kaolin), bronze powder, graphite, vermiculite, phenolic resin, steel fibers, rubber particles, friction dust, soil, and aramid fibers.

Types of Brake Pads
Based on materials, brake pads are generally divided into four types, differing mainly in lifespan and replacement intervals:

1. Organic pads: Made without metals, usually cheapest with the shortest lifespan.
2. Low-metallic pads: Contain small amounts of metal, last longer than organic but are noisier.
3. Semi-metallic pads: Contain higher metal content, have longer life and better performance but cause more disc wear.
4. Ceramic pads: Have the longest lifespan and best quality but are the most expensive.

Mana Tormoz Mashin and Brake Pad Production
Mana Tormoz Mashin Industrial Group proudly produces a wide range of high-quality, noise-free, and non-polluting brake pads with warranty for consumers.

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