Frequently Asked Questions about Semi-Metallic Materials in Brake PadsFrequently Asked Questions about Semi-Metallic Materials in Brake Pads
How to define the friction material formulation for brake pads: It contains steel fibres, porous iron powder, fillers to increase the clash, graphite, coke, lubricant, etc. The content of steel fibres and iron powder is about 40%.
Semi-metallic formulation on friction material. Primary characteristics: 1. Lower cost. 2. High thermal conductivity. 3. Excellent wear resistance.
4. Suitable for heavy-duty braking conditions.
The primary problems of friction materials:
1. Noise, oscillation and roughness simply cause low-frequency noise, accompanied by violent oscillation of the body.
2. More dust (poor degradation at high temperatures).
3. High metal content makes low-temperature and low-speed braking power lacking, and simply causes pedal fatigue.
4. High thermal conductivity and high heating rate will transfer heat to the caliper and its components, and then accelerate the aging of the caliper, piston seal and reset spring. High thermal conductivity simply causes thermal decomposition and high-temperature degradation of conflict materials, which will lead to brake lining dislodgement or rupture.
5. Strong adhesion, not easy to rust. After corrosion, the adhesion or damage is two-layered, and the wear is aggravated.
Volume percentage is the very correct unit of measurement for friction materials. Good formulation engineers should take the initiative to understand the fundamental properties of various raw materials (density, particle size, hardness, moisture, chemical composition, modulus of elasticity), but also should have a clear understanding of the various friction materials on the microscopic and macroscopic impact of friction materials function.
Nowadays, as far as I know in my country, most of the formulation design tests are based on component ratios. In order to avoid the lack of fundamental data on the function of raw materials, it is theoretically difficult to express the link between the quantity of formulation components and the conflict function with simple and clear formulas, such as mixing moments, pressurising moments, pressurising pressures, adherence and degassing moments, grinding methods, two-layer materials, variations in materials and other elements that can readily affect the braking function during the braking process.
With regard to the formulation itself, it is imprecise to determine the proportions of the various raw materials in a theoretical way, nor can we accurately deduce the direct quantitative links between the formulation and the function, which depend primarily on experience gained over time.
