Trends to have a better understanding about tribofilms formed at braking and its relationship with friction material performance has become more relevant to Aftermarket because all regulations have to be met with competitiveness in mind, therefore effective raw materials selection has become crucial.

To understand impact of steel fiber in the composition of the main plateau of the third body, which according to literature, consists of iron oxide nanocrystals, we opted for a semi metallic formulation with 2 different percentages of steel fiber for our automotive disc brake pads.

AK-Master test was used to assess the friction material as well as other techniques for the pad surface: scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), focused ion beam (FIB), and transmission electronic microscope (TEM). It was found that a larger content of steel fiber in the formulation promotes forming of plateaus and a more homogenous tribofilm, these in turn, help improving friction performance. Larger steel fiber contents also increases noise events however they occur at low level decibels (≤ 50 dB) so have null value.

Flores, Alberto*; Lopez Miguel; Avalos, Angelica; García, Oscar FRITEC, Mexico; UNAM, Mexico González, Gonzalo