Inside StopFlex Manufacturing
From Fiber Preform to Validated C/SiC Rotor
Carbon-ceramic brake discs are not coated iron. They are ceramic-matrix composites built on a 3D carbon-fiber reinforcement architecture, then densified via liquid silicon infiltration to form a C/SiC structure. Below is the process in six steps, from preform to validation.
- Long-fiber architecture3D reinforcement for toughness
- LSI densificationMolten silicon to SiC matrix
- Validated performanceHigh-energy dynamometer testing
Quick definitions
C/SiC (carbon-fiber reinforced silicon carbide)
A ceramic-matrix composite where silicon carbide forms the matrix and carbon fibers provide reinforcement.
LSI (Liquid Silicon Infiltration)
A densification method where molten silicon infiltrates a porous carbon preform and reacts to form SiC in-situ.
At a glance
| Step | What happens | Why it matters on the car |
|---|---|---|
| 1 | Continuous carbon fibers form a stable reinforcement architecture. | Improves crack resistance and structural integrity under repeated heat cycles. |
| 2 | Fibers are built into a preform with binder and filler chemistry. | Controls porosity and sets the foundation for later SiC formation. |
| 3 | Preform is consolidated and CNC-shaped close to final geometry. | Near-net shaping improves balance and reduces machining variability later. |
| 4 | Molten silicon infiltrates and reacts, forming a dense C/SiC composite. | Delivers thermal stability and consistent friction at elevated temperatures. |
| 5 | Final machining: vents, faces, and finishing operations. | Controls vibration, runout, airflow, and pad contact quality. |
| 6 | Inspection plus dyno cycles to verify friction stability and heat endurance. | Confidence that the rotor performs under real high-energy stops. |
1 Carbon Fiber Weave
Carbon fiber architecture
We start with high-strength continuous carbon fiber (long fiber) and build a reinforcement architecture designed to carry load in multiple directions. Compared with short chopped fiber mixes, continuous fibers are more effective at bridging cracks and resisting impact-type damage.
2 Resin and Reinforcement
Preform build and binder system
The fiber architecture is combined with a binder system and selected fillers to form a controlled porous preform. This stage is about repeatability: consistent fiber placement, chemistry, and porosity, because porosity directly affects how silicon later infiltrates the structure.
3 Consolidation
Consolidation and near-net shaping
The preform is consolidated (cured and thermally stabilized as required) and CNC-machined close to final geometry. Near-net shaping improves balance control and reduces heavy machining after the composite is fully densified.
4 Silicon Fusion
Liquid silicon infiltration (LSI)
This is the conversion step: under vacuum or controlled atmosphere, molten silicon infiltrates the porous carbon structure by capillary action. Silicon reacts with carbon to form silicon carbide (SiC) in-situ, creating a dense C/SiC composite. Typical LSI processing occurs at very high temperatures, commonly in the 1,550 to 1,700 °C range depending on recipe and geometry.
5 Mill and Polish
Precision machining and surface finishing
Once densified, we complete the rotor features: ventilation geometry, faces, and finishing operations. The goal is tight runout and flatness control, stable pad contact, and predictable airflow, so the driver gets consistent response and low vibration at speed.
6 Quality Control
Inspection and dynamometer validation
Every production batch is inspected for dimensional accuracy and balance, then validated on a dynamometer with repeated high-energy stops. In severe-duty testing, disc surface temperatures can reach the 900 °C class; what matters is friction stability and repeatability from the first stop to the last.
Validation includes repeated high-speed decelerations (for example, 200 km/h / 124 mph down to zero) to verify behavior under sustained thermal load.
Want a kit matched to your vehicle?
Send your Year / Make / Model / Wheel Size. We'll confirm fitment, rotor sizing, and the right hat and pad pairing for your calipers.
