Electron Microscopic Characterization of the Brake Assembly Components (Disc and Pads) from Passenger Vehicles

Atmosphere

Sebastian Gramstat¹  Panayotis Dimopoulos Eggenschwiler²  Daniel Schreiber²  Viola Papetti²  Dmytro Lugovyy³ 

[1] AUDI AG, 84045 Ingolstadt, Germany;Empa, Swiss Federal Laboratories for Materials Science and Technology, Automotive Powertrain Technologies Laboratory, CH-8600 Dübendorf, Switzerland;Horiba Europe GmbH, 61440 Oberursel, Germany;

关键词: precursors of braking particles;    braking pads;    braking discs;    elemental composition;    particle formation;    particle sizes;   

DOI  :  10.3390/atmos13040523

来源: DOAJ

【 摘 要 】

The present work focuses on a detailed analysis of new and used braking friction partners (discs and pads) in order to provide a comprehensive characterization of the source of the airborne particles formed during braking. Scanning electron microscopy (SEM) combined with energy dispersive X-Ray analysis (EDX) was applied to investigate the new brake disc and new and used brake pad components of a passenger vehicle. The pads include at least 21 different substances, involving carbonaceous particles, oxides, sulfides, sulfates and silicates of Al, Si, K, Ca, Ti, Fe, Zr, Sn, less Mg, Ba, Na and, rarely, Bi and Zn, as well as K-titanate. Aramid and phenolic resin are also present, enriched toward the metal interface. The size of the pad constituents extends over a very wide range, from hundreds of µm to a few µm, and goes down to hundreds of nm and, rarely, tens of nanometers. Carbonaceous particles with sizes down to a few tens of nanometers occupy ca. 16% of the total of the pad constituents. Abundant Zr-bearing phases, as well as various other phases involving S, Ca, Mg, Si, Ti and, to a lower extent, Ba and Fe in different combinations, constitute the pad main matrix.

【 授权许可】

Unknown