passenger car floating steel hat Brake Discs

Brake Discs Features

1. Floating Design:

• Thermal Expansion Control: The friction ring and steel hat are connected with micro-clearances (e.g., 0.03–0.05mm) , allowing the ring to expand radially during high-temperature braking without generating internal stress. This prevents warping and cracking, common issues in solid discs.

• Automatic Centering: Floating mechanisms (e.g., pins with wave washers ) ensure the friction ring aligns perfectly with the caliper during braking, optimizing contact and reducing noise/vibration.

2. Hybrid Material Construction:

• Steel/Aluminum Hat: Lightweight hub (e.g., A356 aluminum ) reduces unsprung weight by 15–30%, improving handling and energy efficiency.

• Cast Iron/Composite Friction Ring: High-strength material (e.g., HT250 gray cast iron ) provides excellent heat resistance and wear properties.

3. Enhanced Ventilation:

• Optimized Cooling Channels: Radial or curved vanes between friction ring layers accelerate airflow, reducing peak temperatures by 20–30% compared to solid discs .

• Directional Vane Design: Slots or holes may be angled to create a "chimney effect," expelling hot air outward during rotation .

4. ECE R90 Compliance:

• Performance Equivalence: Must meet or exceed OE braking standards, including thermal fatigue resistance (passing 300+ high-temperature cycles ) and wear limits (<10% thickness loss after 30,000 cycles ).

• Structural Integrity: Rigorous tests for tensile strength, hardness, and dimensional accuracy (e.g., lateral run-out ≤0.1mm ).

5. OE Compatibility:

• Direct Fitment: Engineered for specific models (e.g., BMW M Series, Audi RS, Tesla Model S ), ensuring seamless integration with factory brake systems.

Brake Discs Benefits

1. Thermal Stability:

• Reduced Brake Fade: Floating design and ventilation minimize heat buildup, critical for EVs (which rely on regenerative braking but still require mechanical backup) and high-performance driving .

• Longer Lifespan: Resistance to thermal cracking extends service life by 20–40% compared to solid discs .

2. Weight Reduction:

• Improved Handling: Lighter unsprung weight enhances suspension responsiveness, reducing body roll and improving cornering .

• Energy Efficiency: EVs can achieve 1–2% longer range due to reduced rotational inertia .

3. Safety & Reliability:

• Consistent Braking: Stable friction coefficient (μ=0.35–0.45 across 100–400°C ) ensures predictable stopping power in emergencies.

• Corrosion Resistance: Zinc/nickel plating or ceramic coatings protect steel components from road salt and moisture .

4. NVH Reduction:

• Quieter Operation: Floating mechanisms dampen vibrations, reducing squeal and chatter during light braking .

5. Cost Efficiency:

• Lower Maintenance: Replaceable friction rings (while retaining the steel hat) reduce repair costs by 30–50% compared to full disc replacement .

• 100% critical dimensions, runout and DTV inspection 

• Material physical and chemical inspection

• Test shear strength, compressibility, density, flatness and parallelism 

• Test performance and noise/NVH