Effect of disc materials on brake emission during moderate-temperature braking

Disc material effects on particle emission were investigated under moderate braking conditions using grey iron discs with different microstructures and a ceramic disc. The results demonstrate that brake emissions are strongly affected by disc hardness and the iron transferred to the pad surface. The transferred iron increased brake emissions due to the reduced cohesive strength of the plateaus on the pad surface. The grey iron microstructure also affected the ultrafine particle concentration owing to the graphite flakes. Conversely, the ceramic disc exhibited significantly lower brake emissions due to high wear resistance and no iron transfer to the pad surface.