Do Extreme Temperatures Affect The Operation of The Brake System?

Extreme temperatures (high or low) have multi-dimensional impacts on the brake system. They not only directly affect core components such as brake pads, brake discs, brake drums, and brake shoes, but also alter the friction environment and component fit, further interfering with braking effectiveness. This article will introduce some details.

1. The profound impact of high temperatures on brake components

The harmful effects of high temperatures stem from the cumulative effect of heat generated by braking friction. This is particularly true in scenarios such as long downhill descents in mountainous areas and aggressive driving, where heat accumulates continuously and causes significant damage to various components:

• Deterioration of brake pad/shoe material: The resin binder in conventional semi-metallic brake pads gradually evaporates and carbonizes at high temperatures (above 300°C), weakening the bond between the friction material and the backing plate (or shoe). In severe cases, the pads may fall off or even fall off entirely. Because the friction linings of drum brakes are encased within the brake drum, heat dissipation is poor. They are prone to "thermal aging" at high temperatures—hardening and loss of elasticity on the friction surface. This not only significantly reduces braking force but also creates "hard friction" with the inner wall of the brake drum, accelerating wear on both. Even high-temperature-resistant ceramic brake pads can be damaged by prolonged exposure to extreme temperatures exceeding 800°C, causing a sharp drop in the friction coefficient and irreversible "thermal degradation."

• Physical deformation of brake discs/brake drums: Brake discs are typically made of cast iron or steel. Uneven heating at high temperatures (such as sudden temperature rises in localized friction areas during sudden braking) can generate "thermal stress," manifesting as wavy warping or fine cracks on the disc surface. This deformation can cause the contact area between the brake pad and the disc to fluctuate, resulting in "judder" (steering wheel or pedal vibrations) during braking and even a "sticking" sensation, seriously affecting braking stability. Because the brake drum is a closed, barrel-shaped structure, heat is difficult to dissipate. At high temperatures, it expands significantly, causing the clearance between the brake drum and the brake shoe to increase abnormally. This can initially cause a "longer braking stroke." Later, if the expansion is excessive, it can squeeze the brake shoe's free space, leading to brake drag (increased wheel resistance), creating a vicious cycle of "the more you brake, the hotter it gets," which can ultimately burn out the brake shoe's return spring and other accessories.

• Chain reaction in related systems: High temperatures can simultaneously raise the temperature of metal components near the brake disc, such as the wheel hub bearings and axle shafts, causing grease to melt and lose, exacerbating mechanical wear. Furthermore, high-temperature radiation can affect the performance of the brake fluid. High-quality brake fluid has a high boiling point (typically over 200°C), but low-quality brake fluid easily vaporizes at high temperatures, forming bubbles. This causes "vapor lock," blocking hydraulic transmission and creating the risk of "unresponsive brake pedal."

2.Specific Impacts of Low Temperatures on Braking Components

Low temperatures (such as sub-zero temperatures in winter) primarily affect initial braking response and stability by altering the physical properties of materials and the friction environment:

• Reduced friction efficiency of brake pads and brake shoes: Low temperatures can harden and increase the brittleness of friction materials (especially organic components such as rubber and resin), reducing the initial friction coefficient. This results in "poor cold braking"—a "soft" feel when braking and a significantly longer stopping distance. If the vehicle is parked outdoors, ice or frost may form on the surfaces of the brake pads and brake shoes, causing a momentary slip during initial braking. Drum brake shoes, because they are enclosed in a space, are more susceptible to condensation, potentially freezing the gap between the shoe and the drum, leading to brake sticking ("wheel dragging" during starting).

• Abnormal fit of the brake disc and brake drum: Metal parts contract at low temperatures, increasing the clearance between the brake disc and brake pad, and between the brake drum and brake shoe. This can lead to a longer "loose travel" during initial braking (requiring a longer pedal stroke before braking force is generated). If snow or ice accumulates on the brake disc surface, braking will instantly melt, forming a water film, further reducing friction between the brake pad and the disc. Since brake drums are tightly sealed, ice inside can directly jam the brake shoe's moving mechanism, causing brake failure.

• Collateral Impacts on Other Systems: Low temperatures increase brake fluid viscosity (especially with inferior brake fluid), reducing fluidity and impacting hydraulic transmission efficiency, indirectly weakening braking force. Furthermore, rubber seals in the brake system (such as the brake cylinder piston seal) can harden and crack at low temperatures, potentially leading to brake fluid leakage and further deteriorating braking performance.

3.Summary

Extreme temperatures directly threaten braking safety by altering the properties of friction materials, the physical state of metal components, and the coordination of system components. High temperatures can easily cause component degradation, deformation, and cascading damage, while low temperatures can lead to cold brake failure and delayed response. Therefore, it's important to select appropriate high-performance brake parts based on the vehicle's operating environment (e.g., ceramic brake pads in hot climates, avoid inferior friction materials in cold climates), and regularly check heat dissipation, lubrication, and sealing conditions to cope with the challenges of extreme temperatures.At the same time, it is also very important to choose a suitable, safe and reliable brake-related parts. It is not only related to our driving experience, but also to our personal safety. Therefore, when purchasing brake parts products, we should compare and understand more.The brake parts produced by our EV company are strictly produced in accordance with the standards, with the advantages of high quality, safety and reliability. Welcome to browse our website: https://www.evfriction.com, or you can contact us at any time by jessicabrakes12@gmail.com.