Friction materials typically composed of four main constituents; fiber, resin, filler and additive. The materials in powdery form, mixed and cast into brake linings under high temperature and pressure.
Mixers available in the market are specific to powdery and dry materials that do not stick to each other or to the wall of the mixer. The brake lining meterial composition is powdery but has some tendency to form lumps or stick to the wall of the mixer that will cause inconsistency to the mixture. None of the mixers that are currently available in the market can produce homogenius mixture.