Are passenger car brake discs resistant to high temperatures？

Brake discs are an important part of the braking system. If the braking system is to always slow down the vehicle safely and comfortably - bringing it to a complete stop if necessary - the brake discs must combine with the brake pads to generate braking torque (braking force). This torque is transferred to the wheel hub and from there to the rim. During braking, the kinetic energy of the vehicle is converted into heat due to the friction between the brake lining and the brake disc, thus enabling a reduction in speed. But the vehicle may not be able to withstand the tremendous amount of heat generated in a short period of time, so the ability of the brake discs to dissipate heat becomes an important indicator of their merit. So, are passenger car brake discs resistant to high temperatures？

Materials

High carbon discs

Gray cast iron brake discs

Ceramic materials brake discs

Heat Dissipation Technology

Materials

1. High carbon discs, which are often used today, have optimal thermal conductivity, ensuring more consistent braking performance by keeping the discs running cooler. In addition, high carbon discs have higher resistance to deformation, maintaining vehicle performance

Due to improved thermal properties, high carbon discs offer better stability and increased resistance to deformation and thermal cracking. High carbon discs also offer quieter, chatter-free performance, resulting in an improved driving experience

2. Conventional brake discs made of special gray cast iron (pearl gray cast iron) also have excellent heat dissipation properties. Alloys containing chromium and molybdenum increase wear resistance and improve the thermal cracking characteristics of the material. In addition, the high carbon content increases the heat absorption rate. This is made possible by the high amount of graphite in the microstructure, which leads to a lower temperature in the friction zone and thus to a longer service life of the component. Gray iron has good thermal conductivity due to the graphite phase, which is an excellent thermal conductor.

3. Ceramic materials (carbon fiber ceramics or carbon ceramics) are also increasingly used in the manufacture of brake discs. They have many advantages. For example, ceramic materials have high dimensional stability in all temperature ranges and are suitable for use in high-temperature environments that are instantly generated during automotive braking. Moreover, ceramic materials have a low dead weight, as well as they have an extremely long service life. However, if you only consider this aspect of heat dissipation, you are better off not choosing ceramic materials than the two materials mentioned above. Their obvious disadvantage is their poor thermal conductivity (compared to carbon and iron), which requires the use of special materials for brake linings.

Heat Dissipation Technology

During downhill driving, the friction rings may reach temperatures of up to 700°C (red heat). In addition to the application of better materials, the structural design of the brake can be very effective in enhancing its heat dissipation.

Ventilated brake discs are often used for better cooling (mainly on the front axle). They have a larger surface area and are better suited for heat exchange. Compared to vented discs, solid discs can only dissipate heat more slowly into the environment. The friction rings on vented brake discs are interconnected by ribs or arched webs. The rotation of the brake disc creates air extraction which draws air from the interior of the disc through the vent pipe. This causes the tiny air particles in contact with the surface of the brake disc to absorb heat energy and transfer it outward.

Perforated or slotted brake discs allow for more efficient cooling. These types of discs also benefit from being less sensitive to moisture. However, they are more expensive and in some cases can generate more noise during braking.

Conclusion

By applying excellent heat dissipation materials and advanced design technology to our products, you don't have to worry about the heat dissipation performance of your car brake discs at all. Contact us as soon as possible to choose the car brake discs of your choice.