Impact of the glass fibers addition on tribological behavior and braking performances of organic matrix composites for brake lining

It is shown that addition of glass fibers, in the form of bundles containing tens of fibers, increases thermal properties, enhances normal-compression modulus and allows decreasing wear. Fibers orientation appears to be a key factor with regard to the load-bearing mechanisms, allowing the development of a compacted third body at the rubbing interface when oriented normal to the surface. Conversely, fibers oriented in the sliding plane emerge from the rubbed surface and are not able to improve the load-bearing capacity. Addition of glass fibers helps to reduce thermal localizations, in consistence with higher thermal effusivity allowing better heat absorption and higher normal compressive modulus reducing the anisotropy and improving the pressure distribution.