420*101*40mm Carbon Ceramic Brake Rotor

• Oversized carbon-ceramic brake rotors have long been a technical challenge in the industry: while enlarging diameter and thickness can theoretically boost braking torque and thermal capacity, conventional manufacturing processes often struggle with uniform density, internal residual stress and thermal deformation control on large-format thick discs. Many mass-produced large-size carbon ceramic rotors suffer from premature edge cracking, interlayer delamination and uneven wear under sustained heavy loads, failing to deliver the performance that their dimensions promise.
• Our 420*101*40mm carbon ceramic brake rotor is developed specifically to address these engineering pain points. Built around the three core parameters of 420mm effective diameter, 101mm wide friction surface and 40mm thick disc body, we have optimized material formulation, fiber weaving structure and sintering process for heavy-load conditions, delivering a high-reliability oversized rotor solution for professional endurance racing, 1000HP+ high-horsepower builds and heavy high-performance SUVs.

The performance of a large-size brake rotor does not come from simply stacking dimensions. Every parameter of this 420*101*40mm rotor is calibrated based on braking mechanics and thermodynamics, forming a matched system rather than isolated size indicators.

■ 420mm Effective Braking Diameter

We set the effective friction diameter at 420mm based on the leverage ratio requirement for heavy vehicle braking. For vehicles with a curb weight of over 1.8 tons or power output exceeding 1000HP, conventional 380–400mm rotors require higher caliper clamping force to achieve equivalent braking torque, which not only increases pedal stiffness requirements, but also raises unit pressure on the friction surface and accelerates wear.

The 420mm diameter extends the braking force arm by 5–10% compared with mainstream large-size rotors, achieving higher braking torque output under the same caliper clamping force. It also expands the heat dissipation area, dispersing the heat generated by single braking over a larger surface, lowering the temperature rise rate per braking cycle.

■ 101mm Friction Surface Width

This width is not an oversized design for marketing, but is precisely matched to the effective pad area of competition-grade 8-piston and 10-piston calipers. We found that many large-size rotors on the market use an overly wide friction surface that exceeds the actual contact range of the brake pad. The unworn edge area not only adds useless unsprung weight, but also forms a temperature gradient difference between the contact and non-contact areas, increasing the risk of thermal cracking at the edge.

The 101mm friction surface achieves 1:1 matching with the effective working width of large racing caliper pads, ensuring that the entire friction surface participates in work evenly. This eliminates local overheating caused by partial contact, and also avoids material waste and weight gain from redundant width.

■ 40mm Thickened Disc Body

For continuous heavy braking scenarios, disc thickness directly determines thermal storage capacity and structural rigidity. Under endurance racing conditions, rotors need to absorb dozens or even hundreds of heavy braking heat inputs in a row. Thin discs will quickly reach the temperature threshold and cause thermal fade, and are also prone to thermal deformation and brake judder under high temperature.

The 40mm thick disc body greatly improves the overall thermal storage capacity, which can absorb more heat during continuous braking and maintain stable operating temperature. At the same time, the increased thickness improves the radial and axial rigidity of the disc body, and the thermal deformation rate under high temperature is reduced by more than 30% compared with 36mm thick rotors of the same diameter, effectively suppressing high-speed brake judder and ensuring consistent pedal feel.

Conventional C/SiC carbon ceramic manufacturing process is developed for standard-size rotors. When applied to 40mm thick large-diameter discs, it is easy to have problems such as uneven silicon infiltration density, large internal residual stress and weak interlayer bonding. We have targeted three core process improvements for this specification:

■ 3D Full-Thickness Integral Weaving

For thick discs, ordinary layered lamination weaving will form obvious interlayer interfaces, and delamination is prone to occur under repeated thermal shock. We adopt a three-dimensional integral weaving process, where carbon fibers run through the entire 40mm thickness in the Z-axis direction, forming a three-dimensional network structure without interlayer interfaces.

This structure ensures uniform fiber density from the surface to the core of the disc, and the interlaminar shear strength is increased by more than 40%, fundamentally eliminating the risk of interlayer delamination under long-term heavy load use. We also adjust the fiber orientation angle at the inner and outer edges of the friction surface to enhance the edge stress resistance and reduce edge microcracks caused by alternating cold and heat.

■ Gradient Liquid Silicon Infiltration Process

The biggest difficulty in manufacturing thick carbon ceramic discs is that silicon liquid cannot fully penetrate into the core of the disc, resulting in low core density and inconsistent surface and internal performance. We use a gradient temperature-controlled silicon infiltration process, which controls the infiltration rate and depth of silicon liquid through segmented temperature rise and heat preservation, ensuring that silicon carbide is uniformly generated in the full thickness range of 40mm.

After infiltration, the density deviation of the disc body from the surface to the core is controlled within 2%, far higher than the industry standard of 5%. The uniformly distributed SiC matrix ensures consistent friction coefficient and wear resistance at different depths, and avoids performance attenuation after surface layer wear.

■ Post-Sintering Stress Relief Treatment

Large-size thick discs are prone to large residual stress after high-temperature sintering, which is an important cause of disc deformation and cracking during use. We add a low-temperature long-term stress relief annealing process after sintering, which slowly releases the internal residual stress of the disc body through a 48-hour segmented heat preservation and cooling procedure.

After stress relief treatment, the flatness of the disc body at room temperature is controlled within 0.02mm, and the thermal deformation under 1400°C working condition is less than 0.05mm, which ensures the smooth operation of the braking system under continuous high load and avoids brake judder caused by thermal deformation.

Based on the optimized material and process, this 42010140mm rotor delivers stable and reliable performance in extreme working conditions, and all indicators have been verified by bench tests and track actual measurements.

Thermal Stability

• The rotor can maintain a stable friction coefficient during long-term continuous operation at 1100–1400°C, and the friction coefficient attenuation rate is less than 5% within the working temperature range. Under extreme heavy braking conditions, the transient peak surface temperature can reach 1600°C without structural damage such as melting, cracking or matrix degradation.
• In contrast, high-performance cast iron rotors of the same specification begin to show obvious thermal fade when the surface temperature exceeds 400°C, and the friction coefficient drops sharply above 600°C, and even thermal cracking occurs. The wide high-efficiency working temperature range of carbon ceramic material provides a sufficient thermal safety margin for endurance racing and continuous mountain road driving.

Lightweight Effect

• Despite the oversized diameter and thickened disc body, the overall weight of a single 42010140mm carbon ceramic rotor is only about 40–50% of that of a cast iron rotor of the same specification. The significant weight reduction effectively reduces unsprung mass, improves the response speed of the suspension system, and enhances the wheel grounding performance during high-speed cornering and uneven road driving.
• For track vehicles, the reduction of unsprung mass can directly improve lap performance, and the lightweight effect is more obvious than simply upgrading suspension components.

Durability Life

• The hardness of SiC ceramic matrix is second only to diamond, which brings excellent wear resistance and corrosion resistance. Under daily street driving conditions, the service life of this rotor is 5–8 times that of high-performance cast iron rotors, and it will not rust even in humid coastal areas, and the brake dust generated during use is extremely small, which can keep the wheel hub clean for a long time.
• Under track racing conditions, its service life is 3–4 times that of cast iron racing rotors. For endurance racing teams, it reduces the frequency of rotor replacement during events and long-term training, and effectively reduces the overall operating cost of the vehicle.

This 42010140mm rotor is designed for professional modification and racing scenarios, and supports full-dimensional customized adaptation to meet the needs of different vehicles, calipers and usage scenarios.

■ Installation Adaptation

The rotor requires 21-inch and larger wheel sizes for installation clearance. We support full customization of all mounting parameters, including bolt circle diameter, center bore size, hub offset and bell housing height, which can be seamlessly matched with most mainstream competition-grade multi-piston brake calipers on the market.
Before customization, our engineering team will check the clearance data of the wheel spokes, caliper body and dust cover to ensure that there is no interference after installation.

■ Surface Process Customization

We provide a variety of friction surface process options to adapt to different usage scenarios:

Cross-drilled design: suitable for street and track dual-purpose vehicles, improves heat dissipation and gas discharge, and reduces water slide effect in rainy days;

Slotted design: suitable for endurance racing, cleans the brake pad surface continuously, stabilizes friction coefficient, and has better structural strength than drilling;

Dimpled design: balances heat dissipation and structural rigidity, suitable for heavy vehicles that require long-term continuous braking.

■ Supporting Product Solutions

For B-end customers such as racing teams and modification shops, we can provide a complete set of braking system solutions, including matching carbon ceramic brake pads, high-strength alloy bell housings, steel braided brake hoses, etc. All supporting products are matched and tested with the rotor to ensure the best overall braking performance.

All 42010140mm carbon ceramic brake rotors undergo strict multi-stage inspection before leaving the factory to ensure that each product meets performance and dimensional accuracy requirements.

■ Full Inspection Items

Dimensional accuracy inspection: fully automatic three-coordinate detection of diameter, thickness, flatness and mounting hole position, with tolerance controlled within ±0.02mm;

Dynamic balance test: single-piece dynamic balance correction, with residual unbalance controlled within 0.5g·cm, ensuring no vibration at high speed;

Ultrasonic flaw detection: full-thickness scanning of the disc body to detect internal defects such as pores and delamination, and products with internal defects are 100% rejected;

High-temperature thermal shock test: spot sampling for 50-cycle cold and hot alternating tests to verify structural stability under extreme temperature changes.

■ Supply & Service Support

We support global door-to-door shipping, and bulk orders can be arranged for sea or air transportation according to customer requirements. For long-term cooperative distributors and modification brands, we can provide OEM/ODM services, including customized packaging, brand logo printing and exclusive product parameter tuning.

All products come with a formal quality warranty. During the warranty period, if there are quality problems such as non-human structural damage and abnormal wear, we provide replacement or rework services. Our engineering team provides lifelong technical consultation support to answer customers' questions about installation, use and maintenance at any time.