A Comprehensive Guide to Brake Pads: Materials, Performance, and Selection
In the safety system of a car, brake pads play a crucial and vital role. The quality of their performance is directly related to the safety of drivers and passengers. Understanding the relevant knowledge of brake pads is of great significance to car owners, automotive maintenance personnel, and practitioners in the automotive industry.
I. The Working Principle of Brake Pads
When the driver steps on the brake pedal, the brake master cylinder pushes the brake fluid. By taking advantage of the incompressible property of the liquid, the pressure is transmitted to the brake wheel cylinders of each wheel. The piston of the wheel cylinder pushes the brake pads, making them come into close contact with the high-speed rotating brake disc. At this time, a strong frictional force is generated between the brake pads and the brake disc, converting the kinetic energy of the vehicle's movement into heat energy, thus achieving the deceleration or stopping of the vehicle. For example, when suddenly braking at high speed, the brake pads and the brake disc rub violently, which can quickly reduce the vehicle's speed within a short time.
II. Common Materials and Their Performances
1. Organic Brake Pads (Resin Brake Pads): These are made by pressing various organic materials such as resin, and adding some fillers and additives. The advantages include low noise, which provides a quiet driving experience during braking; good temperature adaptability, with stable performance in low-temperature environments, making them suitable for the frequently stop-and-go driving scenarios in the city; and an economical price, as the cost is lower than other high-performance materials, so they are a common choice for economical vehicle models. However, they have poor wear resistance and are prone to wear under high-temperature or high-load conditions, resulting in a relatively short service life. Moreover, there is a phenomenon of thermal fade in high-temperature environments, where the frictional performance decreases and the braking effect weakens.
2. Semi-Metallic Brake Pads: These are made by mixing metal fibers with organic materials. They have the advantage of strong frictional force, which can provide a high friction coefficient and a remarkable braking effect, making them suitable for sports cars and high-performance vehicles. They also have excellent high-temperature resistance and can still maintain good frictional performance at high temperatures, making them suitable for long-term high-speed driving. Nevertheless, they produce relatively large noise, and there will be an obvious sound during braking. Additionally, the metal components may wear the brake disc, increasing the maintenance cost.
3. Ceramic Brake Pads: These are made of ceramic materials and other fillers. Their low noise characteristic makes the driving experience more comfortable; they have strong wear resistance and a long service life; and they have good thermal stability, with good braking performance under high-temperature conditions, suitable for various driving environments. But ceramic brake pads are relatively expensive. The production cost determines that their market price is relatively high. In low-temperature environments, their frictional force may not be as good as other materials, and their performance will be affected to some extent.
4. High-Performance Brake Pads: These are usually produced by professional brands using advanced materials and technologies, mainly for racing cars or high-performance vehicles. They have extremely high frictional performance and can maintain excellent braking effects even under extreme conditions. They are specially designed to adapt to high-speed driving and intense driving. However, they generate a large amount of heat during intense driving and require a good cooling system to cooperate. For ordinary urban driving, there may be a problem of excessive wear.
III. How to Select Suitable Brake Pads
1. Consider Driving Habits: For frequent stop-and-go driving in the city, it is recommended to choose organic brake pads or ceramic brake pads, as their low noise and good low-temperature performance are more suitable. If you like high-speed driving or occasionally drive on mountain roads, semi-metallic or high-performance brake pads can meet the higher requirements for braking performance.
2. Combine with the Driving Environment: If the area where you are located frequently experiences high temperatures or has many slippery roads, ceramic or semi-metallic brake pads with good high-temperature resistance are a better choice.
3. Based on the Budget: The price range of brake pads is wide, from economical organic brake pads to high-performance ceramic brake pads. Determining the budget first can help you make a more accurate choice.
4. Refer to the Type of Vehicle: Sports cars usually require high-performance brake pads, while family cars can choose economical and practical products.
