White corundum can be used in the production of automotive brake pads. Due to its high hardness, high-temperature resistance, corrosion resistance, and excellent wear resistance, white corundum is often used as a reinforcing component in friction materials to improve the wear resistance and thermal stability of brake pads. The following is a detailed analysis:
1. Application of White Corundum in Brake Pads
As a wear-resistant reinforcing material: White corundum (primarily composed of Al₂O₃) has high hardness (Mohs hardness 9.0, Knoop hardness 2000-2200 kg/mm²) and excellent wear resistance, making it suitable for use in the friction layer of brake pads, effectively reducing wear and extending service life.
High-temperature resistance: White corundum has a melting point of up to 2250°C and a maximum operating temperature of 1900°C. It maintains stability even in the high-temperature friction environments of brake pads, preventing softening or failure caused by high temperatures.
Chemical stability: White corundum is resistant to acid and alkali corrosion, remaining stable even in strong acids (such as aqua regia) or bases, making it suitable for brake pads operating under complex operating conditions.
2. White Corundum in Brake Pad Formulations
In patent CN105670564A, white corundum (1-3 parts) is used as a component of a copper-free friction material, combined with steel fiber, modified phenolic resin, and silicon carbide to improve the brake pad’s thermal crack resistance and wear resistance.
The particle size of white corundum (e.g., 46#, 54#, 60#, etc.) can be adjusted according to the brake pad’s requirements. Coarser particle sizes (e.g., 46#) are suitable for enhancing friction performance, while finer particle sizes (e.g., 220#) are used for fine polishing.
3. Comparison of White Corundum with Other Abrasives
Compared to brown corundum, white corundum has higher hardness but slightly lower toughness, making it more suitable for brake pads requiring high precision and high wear resistance.
Compared to silicon carbide, white corundum has better chemical stability and is suitable for copper-free, environmentally friendly brake pad formulations.
4. Practical Application Examples
Henan Sicheng Abrasives Tech Co., Ltd. provides white corundum 46# specifically for automotive brake pad molding compounds, suitable for reinforcing the wear-resistant layer. In the manufacture of resin cutting discs and grinding wheels, white corundum is also used in the processing of automotive parts such as brake cables and brake pads, further demonstrating its suitability for use in friction materials.
Conclusion
Due to its high hardness, high-temperature resistance, and wear resistance, white corundum is well-suited for the production of automotive brake pads. It holds particular value in the formulation of high-performance, copper-free, and environmentally friendly brake pads.