Application of Chopped Glass Fiber 6mm in Brake Shoes Production
In the field of brake shoes manufacturing, Chopped Glass Fiber 6mm has found its way into brake shoes mixtures and mixes, playing a significant role in determining the performance of brake shoes friction materials. This fiber, with its unique characteristics, brings both advantages and disadvantages to the table.
Technical Parameters
- Tensile Strength
- Chopped Glass Fiber 6mm generally has a tensile strength in the range of 1500 – 2000 MPa. This high tensile strength is crucial as it provides reinforcement to the brake shoes friction materials. For example, during heavy braking, when the friction materials are under a shearing stress of up to 600 MPa, the 6 – mm glass fiber can effectively resist the stress and prevent the matrix from cracking.
- Thermal Stability
- It can withstand temperatures up to 550 – 650°C without significant degradation. In high – speed braking situations where the temperature of the brake shoes can rapidly rise to 450°C, the 6 – mm glass fiber remains stable, ensuring the integrity of the friction material.
- Aspect Ratio
- With a length of 6mm, the aspect ratio (the ratio of length to diameter) of the chopped glass fiber typically ranges from 200 – 300, depending on the fiber diameter. A higher aspect ratio, such as 250, allows for better load transfer within the brake shoes mixture, enhancing the overall mechanical properties of the friction material.
Advantages
- Exceptional Mechanical Reinforcement
- When incorporated into brake shoes mixtures, Chopped Glass Fiber 6mm can significantly increase the flexural strength of the brake shoes friction materials. Tests have shown that the flexural strength can be enhanced by 40 – 60%. For instance, in a standard flexural strength test, the friction material without the fiber had a flexural strength of 25 MPa, while the one with 15% (by weight) of 6 – mm glass fiber achieved a flexural strength of 35 – 40 MPa. This reinforcement makes the brake shoes more durable under extreme braking conditions.
- Superior Heat Dissipation
- The 6 – mm glass fiber contributes to better heat dissipation in the brake shoes. In a series of continuous braking tests at a speed of 120 km/h for 8 minutes, brake shoes with Chopped Glass Fiber 6mm maintained a friction coefficient of 0.38 – 0.42, while those without the fiber experienced a significant drop in the friction coefficient to 0.22 – 0.27 due to overheating. This shows that the fiber – reinforced brake shoes can better resist brake fade.
- Outstanding Abrasion Resistance
- Brake shoes with 6 – mm chopped glass fiber exhibit remarkable abrasion resistance. In a 150,000 – kilometer driving simulation test, the wear depth of the friction material with the glass fiber was only 2 – 3 mm, while that without the fiber reached 5 – 6 mm. This indicates a 50 – 60% reduction in wear rate, resulting in a longer service life for the brake shoes.
Disadvantages
- Higher Cost
- The production and processing of Chopped Glass Fiber 6mm are more complex compared to shorter – length fibers, leading to a higher cost. Incorporating this fiber into brake shoes mixtures can increase the overall production cost by 30 – 40%. This cost increase can be a deterrent for manufacturers aiming for cost – effective mass production.
- Dispersion Difficulties
- Due to its longer length, 6 – mm chopped glass fiber can be more difficult to disperse uniformly in the brake shoes mixture. Uneven dispersion can lead to inconsistent mechanical properties in the friction material. For example, in some cases, areas with a higher concentration of fibers may be overly rigid, while areas with fewer fibers may be more prone to wear.
- Environmental Impact
- Similar to other glass fibers, Chopped Glass Fiber 6mm is non – biodegradable. Improper disposal of brake shoes containing this fiber can cause long – term environmental pollution. Additionally, recycling these brake shoes is more challenging compared to those made with biodegradable materials, adding to the environmental burden.
In conclusion, Chopped Glass Fiber 6mm offers significant advantages in terms of mechanical reinforcement, heat dissipation, and abrasion resistance in brake shoes production. However, its high cost, dispersion issues, and environmental impact need to be carefully considered. Manufacturers must balance these factors based on their specific production requirements and market demands.