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The friction material is arguably at the heart of any brake system, with its properties taking one of the most important roles in defining its performance characteristics. High performance applications, such as race track capable brake systems in high powered vehicles, exert considerable stress on the friction materials, in the form of very high heat flux loads, high clamp and brake torque loads, and high operating temperatures. It is important, for high performance applications, to select capable friction materials, and furthermore, it is important to understand fully what operating conditions the friction material will face in the considered application.

In racetrack conditions, brake systems are subjected to extreme energy loads and energy load distributions. This can lead to very high friction surface temperatures, especially on the brake corner that operates, for a given track, with the most available traction and the highest energy loading. Individual brake corners can be stressed to the point of extreme fade and lining wear, and the resultant degradation in brake corner performance can affect the performance of the entire brake system, causing significant changes in pedal feel, brake balance, and brake lining life. It is therefore important in high performance brake system design to ensure favorable operating conditions for the selected brake corner components under the full range of conditions that the intended vehicle application will place them under. To address this task in an early design stage, it is helpful to use brake system modeling tools to analyze system performance.

Brake-based park systems, where an electric parking brake system becomes fully responsible for vehicle immobilization and enables elimination of the traditional driveline-based parking pawl, has increased in popularity, especially in full Electric Vehicles. At face value, the promise of saving mass, cost, and critical packaging space in an electric drive unit is compelling. However, this must be weighed carefully against less obvious impacts, which include engineering in added redundancy, significant changes in “real world” duty cycle of EPB components, risk of brake pad and rotor crevice corrosion, and perhaps most acutely because it affects every drive cycle, the impact to residual drag and therefore vehicle energy use.