Tribological performance of friction braking systems for minimised brake emission

Compared to the massive effort aimed at reducing diesel particulate emissions, wear emissions from friction brakes have received far less attention. The alternative electric powertrain vehicles usually employ some form of regenerative braking system but they will continue to require friction brakes for conditions where the regenerative system fails or is less effective such as when the vehicle comes to rest at traffic lights. It is likely therefore that wear emissions from friction brakes, alongside those from tyre/road interactions, will become the major source of atmospheric particulate pollution from road transport in the years ahead.

With the emergence of friction materials development, there is a need to fully understand brake pad/disk interactions between current and future friction materials and new materials technology for applications in automotive, high speed rail, airspace, etc. This project will build on our ongoing research and will aim to provide an in-depth understanding of the interactions between the brake pads and disks leading to particle emission with different natures and characteristics as a result of wear and corrosion in particular. This would provide a knowledge on the mechanisms of particles generation and their characteristics and could present valuable guidelines to minimize particulate emissions from friction brakes whilst reducing the unsprung mass of the vehicle and hence reducing CO2 emissions.