Ferroferric Oxide Black, a magnetic iron oxide compound, has found its application in the production of brake shoes. When integrated into brake shoes mixtures and mixes, it exerts a notable influence on the performance of brake shoes friction materials. Let’s explore its technical parameters, advantages, and disadvantages in detail.

Ferroferric Oxide Black is strongly ferromagnetic. Its saturation magnetization can reach up to 92 – 98 emu/g. This magnetic property can be utilized in some advanced braking systems. For example, in electromagnetic braking assistance systems, the ferromagnetic nature of the oxide can interact with magnetic fields to enhance the braking force modulation.

On the Mohs scale, it has a hardness of about 5 – 6. This moderate hardness contributes to the wear – resistance of the brake shoes friction materials. In a wear – test over 50,000 braking cycles, brake shoes with 15% Ferroferric Oxide Black by weight showed a wear depth of 1 – 1.5 mm, while those without it had a wear depth of 2 – 2.5 mm.

The thermal conductivity of Ferroferric Oxide Black is around 9 – 11 W/(m·K). During the braking process, when heat is generated at the friction surface, this thermal conductivity helps in dissipating heat. In a braking experiment where the temperature at the friction surface without the oxide reached 350°C, the addition of Ferroferric Oxide Black reduced the peak temperature to approximately 320°C.

In brake systems that incorporate magnetic – based technologies, the ferromagnetic property of Ferroferric Oxide Black can significantly enhance the braking force. In a test of an electromagnetic – assisted braking system, the addition of 20% Ferroferric Oxide Black to the brake shoes friction material increased the braking force by 25 – 30%, providing more efficient braking performance.

Thanks to its moderate hardness, Ferroferric Oxide Black improves the wear resistance of brake shoes. Brake shoes with this oxide can last 1.5 – 2 times longer than those without it in normal driving conditions. This reduces the frequency of brake shoe replacement, saving both time and cost for vehicle owners.

It can maintain its physical and chemical properties at relatively high temperatures. In a high – temperature test up to 400°C, Ferroferric Oxide Black in the brake shoes friction material did not show any significant degradation, ensuring the stability of the braking performance even under extreme heat conditions.

Ferroferric Oxide Black can be oxidized in the presence of oxygen and moisture over time. This oxidation can lead to a change in its magnetic and physical properties. In an environment with high humidity (above 80% relative humidity) and oxygen exposure for 6 months, the saturation magnetization of the oxide decreased by 15 – 20%, which may affect its performance in magnetic – assisted braking systems.

Compared to some specialized friction – enhancing materials, Ferroferric Oxide Black has limited ability to precisely modulate the friction coefficient. In different braking conditions, the friction coefficient of brake shoes with this oxide may fluctuate more than desired. For example, during sudden braking from high – speed to low – speed, the friction coefficient can vary by ±0.1, which may cause a less – smooth braking experience.

Ferroferric Oxide Black is, as its name implies, black. This color may limit its use in some applications where specific color requirements for brake shoes exist. For example, in luxury vehicle manufacturing, where brake components are sometimes visible and need to match the aesthetic of the vehicle, the black color of the oxide may not be suitable.

In summary, Ferroferric Oxide Black offers advantages such as enhanced braking force in magnetic systems, good wear resistance, and thermal stability in brake shoes production. However, its susceptibility to oxidation, limited friction modulation, and color limitation need to be carefully considered. Brake shoe manufacturers should weigh these factors based on the specific requirements of their products and the target market.