Natural Fibers in Friction Materials

This paper will discuss whether natural fibres such as flax, hemp kenaf and jute provide a viable alternative to existing fibrous materials in modern friction formulations. Natural fibres are a sustainable resource and have been shown to have a high specific strength while costing a fraction of the price of some man-made fibres currently used in friction materials. The role of fibres within friction materials is diverse. They are reported to act as processing aids, friction stabilisers, as reducers of both wear and noise and also aid in maintaining the mechanical integrity of friction materials at high temperatures. This behaviour depends on both material properties and the morphology of the fibre. One fibre commonly used by the friction industry is Aramid both in pulp and monofilament form. This research has analysed a typical friction material used for cars and commercial vehicle applications containing aramid as the main fibrous ingredient - and 11 other raw materials. The role of Aramid has been elucidated by investigating the function of the fibres from early mixing stages through to the final performance of a finished pad.