Tribological performance evaluation of automotive brake discs manufactured from boron-doped titanium dioxide-reinforced aluminum composite

Abstract

In this study, we manufactured a boron-doped titanium dioxide (B-TiO2)-strengthened aluminum brake disc via the die-casting technique to see if it could replace conventional brake disc made from gray cast iron material in automobiles. This study conducted braking experiments at room temperature under various applied loads, ranging from 320 to 1600 N (0.067 to 0.338 MPa), and with sliding speeds ranging from 0.65 to 2.46 m/s. The study compared the tribological performance of a B-TiO2-strengthened aluminum brake disc with that of a conventional brake disc. To characterize the microstructures, wear mechanisms, and composition of the friction layer, we used a scanning electron microscope (SEM) equipped with an energy dispersive spectrometer (EDS). The results illustrated that the average friction coefficient of a B-TiO2-strengthened aluminum brake disc was 15–32 % higher than that of the conventional brake disc. Additionally, both the aluminum alloy disc and its brake lining demonstrated higher wear losses compared to the conventional brake disc and its brake lining. However, the B-TiO2-strengthened aluminum brake disc exhibits a 30 % reduction in wear losses when compared to the aluminum alloy disc alone. Moreover, it boasts an 8.66 % higher compressive strength compared to the aluminum brake disc alone. The friction layer formed on the rubbing interfaces enhances and stabilizes the brake friction coefficient. Concisely, this study serves as a starting point for future research into the applicability of aluminum brake discs in automotive applications.