Selective Composite Lightweight Aluminum Brakes
Metal Matrix Innovation's manufacturing process provides numerous benefits over current competitors as well as past attempts to produce metal matrix composite (MMC) brake discs. Although stir casting has been available for many years, there has yet to be a successful, sustained disc brake product using this technology. Our process is highly customizable, offering the ability to tweak the ceramic preform to change the material properties of the final composite. The properties that we can change are hardness, porosity, strength, and machinability. Our optimized production method also results in minimal scrap and an overall cheaper manufacturing process.
Uniform Distribution of Reinforcement
In stir cast products, the difference in density between silicon carbide (SiC) and aluminum (Al) leads to an unpredictable concentration of SiC particles throughout the casting. Our preform process guarantees an even distribution of roughly 40 vol% SiC and 60 vol% Al for a much more uniform friction surface when compared to stir cast MMCs. This results in a braking surface with nearly double the silicon carbide content compared to stir cast MMCs, providing better wear resistance and more stable friction.
High Pressure Aluminum Casting
MMI’s high pressure aluminum casting process produces a unique, high-integrity single casting composed of two material compositions. The preform is uniformly infiltrated with aluminum during the same casting process that forms the remainder of the brake disc. This creates a single casting made of two distinct sections: one monolithic aluminum and the other reinforced metal matrix composite. Our casting process ensures a high-integrity, near net shape casting with minimal porosity.
Selectively Placed Composite
Our preform process enables the composite to be placed only where it is needed, at the friction surface. No silicon carbide reinforcement is wasted in locations that wear resistance is not needed, such as the “hat” section of the brake disc. This minimizes the amount of reinforcement material needed, and also greatly reduces machining costs as the monolithic aluminum can be easily machined with standard tooling.
This highly customizable process allows us to design the ideal brake disc. We have engineered Alumatrix for weight reduction, corrosion resistance, and durability.