Brass in brake linings: Key considerations for its replacement

Following the ban of its use in brake linings, asbestos has been replaced by various materials based on industrial feedback and trial and error, but without any real understanding of how it affects contact during braking. As copper too will be prohibited in a few years' time, we set out to study the influence of one of its alloys, namely brass. A simplified brass-containing material was developed for this purpose. This material has an anisotropic microstructure and consequently exhibits anisotropic mechanical behavior and increased thermal diffusivity. It displays good tribological behavior at moderate and high temperatures. A surface analysis shows that the contact area is very effective at trapping third bodies and developing secondary plateaus, which provide good conditions for stabilizing friction to a high degree, even at high temperatures.